COVID-19 is a contagious respiratory disease caused by a coronavirus, from the same family that includes SARS, MERS, and some varieties of the common cold. The virus was identified in December 2019, has spread around the world, and was declared a pandemic in March 2020. As of May 2023, there have been 688 million confirmed cases and 6.87 million deaths reported; these are inevitably an undercount. COVID-19 is widespread around the world, and many cases are not recorded.
The disease is more dangerous and more contagious than the seasonal flu, and less dangerous but more contagious than SARS and MERS. Older people and those with underlying conditions (especially respiratory problems or a weak immune system) are the most at risk of complications including death. However, young healthy individuals have also been hit seriously and even died. An infection can cause long term effects even in people who have otherwise mild symptoms.
Simple precautions — such as frequent hand washing or use of a hand sanitizer, facemasks, and when possible avoiding crowded places or keeping your distance from others — will reduce the risk of infection. A variety of restrictions have been used to combat the spread of the virus. Many countries required COVID vaccination, testing, or quarantine as a precondition for entry, and some such as Thailand require visitors to have approved health insurance. Within countries, masks have sometimes been legally required, some businesses were required to shut down at times, and various quarantine conditions were imposed.
The greatest restrictions were in 2020 and 2021; by mid-2022 many countries began to loosen these measures, and this has continued into 2023. As of May 2023, WHO has declared that the pandemic is no longer an international emergency. Some countries, such as Japan, no longer require vaccination as a condition of entry but others, such as the Philippines, do.
Symptoms and prognosis
Common symptoms include a fever, cough, loss of appetite, and fatigue. Other less common symptoms include shortness of breath, nausea, vomiting, diarrhea, sputum production, muscle pain and loss of sense of smell. Some patients have very mild symptoms, similar to a cold, and some have no symptoms at all, but these people are still contagious. Most cases recover without special treatment, but some become seriously ill.
Serious complications include pneumonia, acute respiratory distress, and multi-organ failure leading to disability or death. As of May 2023 the fatality rate for all reported cases to date is about 1%. The rate was considerably higher early in the epidemic, but has come down as treatment methods have improved and vaccination, which reduces the risk of serious complications, has become common. Quite likely it is now below 1% for new infections.
Those most at risk of complications are the elderly and those with weakened immune systems or underlying health conditions like cardiovascular disease, diabetes, hypertension, chronic respiratory disease, and cancer. Not many cases are reported in children and most of these are mild or moderate, though a significant fraction do get pneumonia.
The time between being exposed to the virus and the emergence of symptoms (incubation period) is typically between 2 and 14 days. The disease is most contagious during the first three days of symptoms, but it can also be transmitted without symptoms. There have been recorded cases of people getting infected more than once, though reinfections are usually milder than the first infection.
Long-term effects for people who have recovered remain unclear, but there is evidence of reduced lung capacity in some recovered patients. There is also some evidence that people may develop Kawasaki disease-like symptoms after recovering from COVID-19, while the disease has also been linked with an increased risk of thrombosis, blood clots which may cause a heart attack or stroke..
COVID-19 vaccines are available in most countries, though still easier to find in richer countries than in poorer ones. Get vaccinated as soon as you can, in order to protect yourself and those around you. Vaccination is not a guarantee against getting infected, against spreading COVID to others, against complications, or against death, but it does significantly reduce all those risks.
For most vaccines, the protection is best after having had two doses with several weeks in between and then waiting two weeks for antibodies to develop. If you are going to travel or visit risky areas, you should try to have your doses in time for that.
There are over half a dozen vaccines in widespread use and more still undergoing clinical trials. Vaccines that have been approved by the WHO include mRNA vaccines (Pfizer/BioNTech and Moderna), viral vector vaccines (AstraZeneca and Johnson & Johnson) and more traditional inactivated virus vaccines (Sinopharm, Sinovac and Bharat Biotech). Several others are going through the approval process. While all WHO-approved vaccines are very effective in preventing serious complications and death, their efficacy when it comes to preventing mild and asymptomatic cases varies between vaccines and virus variants.
Depending on the country, proof of vaccination may be necessary for travel. Each country has its own rules, including a list of which vaccines they accept. In general, the "Western" vaccines (BioNTech/Pfizer, Johnson & Johnson, Moderna, AstraZeneca) will open the most doors. Some countries' restrictions include a maximum time since the most recent dose, effectively making boosters a requirement for some travellers. Some require a minimum time since completing the required vaccinations, so last-minute vaccinations don't help. For the Chinese vaccines, Sinovac or Sinopharm, Singapore requires you to have three doses, with the third dose 3 months after the second, in order to be considered fully vaccinated.
Evidence of vaccination may not exempt you from other measures being imposed, including quarantine, as you may still spread the disease. On the other hand, lack of vaccination will exclude you from some countries and may mean stricter testing or quarantine requirements in others.
Whenever possible stay outside and avoid public indoor spaces, especially crowded spaces.
Many governments around the world have advised their citizens not to travel unnecessarily amid the pandemic. Particularly avoid cruise ship travel. Travelers who have not yet been fully vaccinated against COVID-19, especially older travelers and those with certain medical conditions, are most at risk and should avoid travel, especially long plane flights, visits to crowded places, and cruises, even outside of severely affected areas.
In affected areas, you should practice physical distancing (social distancing). This means minimising contact with others by keeping a distance of six feet or two meters from them and avoiding gathering together in groups. Measures you are encouraged to take include working from home whenever possible, avoiding crowds and avoiding leaving your home unless necessary. If you must go out, try to stay at least 2 m (6 ft) away from other people. In many places these measures are required. Some areas prohibit gathering in large groups; others prohibit all group gatherings.
COVID-19 is transmitted through the air and through objects, and it is contagious even without symptoms. Follow hygiene practices like for flu prevention. These include:
- Wear a mask in public in areas where transmission is widespread, and especially where physical distancing isn't possible (such as shops and public transportation). Medical masks are recommended for people over 60, people with underlying conditions, those who are suspected of carrying the disease, and those who are in close contact with infected people. Wearing a mask is required in some countries and cities in an effort to reduce community transmission. In some areas any sort of face-covering is accepted, such as a scarf, or just a T-shirt. Even if you aren't worried about catching the virus, you should still cover your face, to avoid transmitting it to others in case you have an asymptomatic infection. Many countries are experiencing shortages of surgical masks.
- Make sure to use the mask correctly. The mask should cover your nose and mouth and fit without gaps. Wash your hands before putting on the mask and avoid touching the mask while wearing it. If you do touch it, wash your hands immediately afterwards. When the mask becomes damp, discard and replace it. Remove it from the back, throw it away, and then wash your hands.
- Increasingly mask mandates specify that a FFP2 (KN95) mask needs to be worn. Those may be scarce in certain times and places. Reuse, while common, is still not proven as perfectly safe (a common recommendation is to let the mask rest or dry in ambient air for seven days before reusing) so stock up before you go to a place that mandates those masks.
- Open windows of rooms and vehicles when possible, for good ventilation and airflow.
- Frequently wash your hands with soap and water, and then dry your hands on a clean towel. As coronaviruses are enveloped viruses, washing your hands with soap kills the virus by disrupting the mostly fat-based viral envelope. Effective hand washing requires rubbing your hands for at least 20 seconds. Drying your washed hands physically removes some germs from your skin (so don't skip that step, and don't share towels).
- If soap and water are not available, then use a >60% alcohol-based hand sanitizer. Alcohol is a quick germ-killer, but it's not quite instant, so this still requires the same 20 seconds of rubbing your hands together, making sure that every single scrap of skin gets wet, and then you have to wait about another minute, for the alcohol to completely dry.
- Disposable gloves can also be useful if you have to handle multiple things others may have handled or sneezed on when it's not convenient or possible to wash your hands. One example would be going to a public building where you would have to open doors and push elevator buttons. After you're done using them, take them off touching them minimally (they will naturally fold inside out, hiding the outer possibly infected surface, and the one first off can be left inside the other), discard them and wash your hands as instructed above.
- Keep your hands away from your eyes, nose and mouth. Most people touch their faces every few minutes, all day long. Try to do this less, and try to wash your hands before touching your face. Also, try to avoid touching surfaces you don't have to touch in the first place, at least with your bare hands.
- Cough and sneeze into your elbow or a tissue, and then immediately throw away the tissue and wash your hands.
- Keep your distance. Formerly 1–2 m was recommended: Could you touch the other person's hand without taking a step towards that person? If the answer is yes, then you're too close. Now the recommendation is 2 m, which would be more like your full length with stretched arms.
- Don't stand or sit near people who might be sick.
Other actions include:
- Clean objects and surfaces that a lot of people touch, such as doorknobs, phones, and television remotes with regular household cleaner. Disinfect the surfaces with a suitable disinfectant, such as diluted household bleach.
- Stay home when you are sick, and avoid contact with other people until your symptoms are gone. In many cases you should book a test at once, but avoid putting others at risk when going to the test site.
- Do not share personal items that come into contact with saliva, such as toothbrushes, eating utensils, drinks, water bottles, and towels.
- The practice of serving yourself from a common plate with your own chopsticks, common in China, should be avoided. Instead, you should use communal chopsticks to prevent contact with saliva.
- Greet people without touching them. Avoid hugs, kisses, handshakes, fist bumps, and any other contact. If it's impossible to avoid contact, then wash your hands both before and after.
- Take a note of the locations you visit and make sure you complete the location's contact tracing register (if they have one). If someone catches COVID-19, public health officials can use the information to identify those at risk of catching the virus through close contact and requiring them to self-isolate and get tested. Ultimately, the aim of contact tracing is to identify chains of transmission, allowing public health officials to get ahead of the chain and stopping further spread.
Avoid crowded areas, especially enclosed areas without much air circulation, such as conferences, performances, shopping malls, public transportation, and religious services. Events which involve a large scale gathering of people, from religious pilgrimages to music concerts, have been canceled around the world, in an effort to contain the spread of the virus. Tourist attractions, businesses, and transportation may be closed. Some canceled events, especially performances, sporting events, and classes, are being moved online, which means you can experience them without traveling.
At petrol/gas stations, use gloves or wipe down the handle with a disinfectant wipe if you can. After filling up, clean your hands with hand sanitizer.
Infections can spread easily on cruise ships, and on-ship medical care is limited. Amid a cruise ship outbreak, quarantines and docking are challenging partly due to the large numbers of people aboard. Even cruise ships without confirmed cases have been denied permission to dock due to virus fears, and in the high-profile case of the Diamond Princess in Japan, hundreds of people were infected on the ship.
- See also: Flight and health
On a plane, follow the same hygiene practices as anywhere else: wash hands frequently, or use alcohol-based hand sanitizer if it's not convenient to leave your seat, wear a mask, and avoid touching your face.
Researchers have found that passengers in window seats have less risk of contact with sick people. Avoid moving around the cabin during the flight.
After washing your hands and before sitting down, use disinfectant wipes to wipe down the area around your seat. Wipe hard surfaces, and if your seat is leather you can wipe that too. Don't wipe a cloth seat, as the moisture can make transmission easier. When using disinfectant wipes, follow the instructions on the packaging. And remember, viruses enter through your mouth, nose, and eyes – wiping down the area doesn't hurt, but it's not a substitute for proper hygiene. Wash your hands and avoid touching your face. And use a tissue to touch the touch screen or other controls.
When using the lavatory, use paper towels to turn off the faucet and open the door, then throw them away.
Airlines are taking steps to reduce transmission and keep passengers safe. For instance, these may include cleaning facilities more frequently, allowing or requiring flight attendants to wear masks, and serving prepackaged instead of freshly heated meals. Some airlines require passengers to wear masks and may remove you from the flight if you refuse. If a group of passengers is connecting from an area with a severe outbreak, the flight attendants may be able to seat them away from the rest of the passengers (and if you were recently in a high-risk area, consider telling the flight attendants for this reason). If possible, flights may keep middle seats or alternating rows empty to increase distance between passengers. Some airlines are allowing passengers to cancel if the flight gets above 70% capacity.
You may be prohibited from changing seats on the flight. This is so that, if someone on the flight turns out to be infected, the authorities can track down the people who were sitting near them for testing or quarantine.
Testing and treatment
If you believe you may be infected, call a hospital or local emergency medical services instead of going in person to avoid infecting others. Mention your symptoms and travel history. Wear a medical mask and follow the instructions of authorities and doctors. Don't try to self-medicate with unproven treatments.
Tests are available to see if you are infected with COVID-19. Many of them use a technique called "polymerase chain reaction", so you'll see references to "PCR tests". Countries' testing policies vary: in some places you can only get tested with a good reason (such as symptoms or recent travel), but in other places you can get tested on demand. Testing may be free, covered by insurance, or you may have to pay for it yourself. Some countries impose compulsory testing to locations that COVID-19 infection clusters emerge, and you may face criminal liability if you don't take a test. Rapid antigen tests may not detect all COVID-19 positive individuals, however, you should assume yourself to be infectious if the rapid test indicates a positive result for COVID-19.
Some countries require a recent negative PCR test for travel. The tests are not completely reliable, especially if you take them too soon or too late after infection. That's why quarantine may still be required. Public testing facilities (intended for those with symptoms) may be unable to provide tests for travel. Make arrangements in advance to get a suitable test on the correct day, with appropriate documentation. In many cases, you will have to pay for the tests yourself.
Antibody tests are also available to determine if you have COVID-19 antibodies (an indication that you have been infected at some point in the past). They are not completely reliable either, and it's not yet clear to what extent antibodies provide immunity. Nonetheless, an antibody test may also be a requirement for travel to some countries.
In some countries, the healthcare system has been stretched to the point of not being able to handle the sheer number of patients, and there is a chance you may be refused treatment due to the lack of available medical staff, supplies or equipment. This also means that if you have need medical care for a reason unrelated to COVID, you may have trouble getting it.
|If you hear of a plague in a land, do not enter it. If it breaks out in a land where you are, do not leave.
—Prophet Muhammad, Sahih Muslim 2218
If you're planning to travel, especially internationally, stay up to date about any pandemic-related restrictions and requirements in your destination, your home country, and any transit stops. Restrictions vary widely and can change frequently. As of May 2023, a number of countries still require proof of vaccination or a negative test result for entry, but the most severe restrictions have generally ended.
Passenger registration forms
Some countries and regions require incoming passengers to fill out a form with their personal information, recent travel history, and intended lodging upon arrival. This is to ensure you're aware of any restrictions, to determine whether you need to quarantine, and to make sure the authorities can contact you if another passenger tests positive. In some cases the form must be filled out online before you arrive, so check the official government website a few days before you depart.
Many countries have severely limited flights, ships, and border crossings, especially to and from severely affected areas. Even more countries have imposed restrictions on arriving travelers, often requiring proof of vaccination or proof of a negative test result shortly before travel. (In some cases these requirements may be waived if you can prove that you have recently recovered from COVID-19. On the other hand, if you've recently recovered but the place you're travelling to requires a negative test result, it's unfortunately possible that you might continue to test positive for weeks or even months after you're no longer contagious.) You may also be required to quarantine, often for 14 days or more and possibly at your own expense. Even if a mandatory quarantine is not imposed, you may be asked to "self-quarantine" by staying at home and not interacting with other people. Many restrictions vary depending on where travelers are coming from or their citizenship or residency, but many countries apply them to all incoming travellers. Some countries have even prohibited all or almost all foreigners from entry. At the very least, expect to be screened and questioned about your travel history and any symptoms.
The most reliable source of restrictions information should be published on each country's foreign ministry or customs and immigration website. For EU countries, the most detailed database/map of up-to-date restrictions is listed on the official website of the European Union. Keep up to date — outbreaks and travel restrictions are constantly changing.
Consider making refundable reservations in case the changing situation forces you to change your plans. Avoid buying tickets with a connection in an affected area – even merely changing planes might make you subject to restrictions. Since COVID-19 is now a pre-existing event, travel insurance won't cover you if you have to cancel or change your plans.
Flights, trains, and buses may get canceled with little notice, either due to the disease's spread and ever-changing entry restrictions, staffing shortage or simply because there aren't enough travelers to fill the seats. You might be denied boarding due to a restriction you weren't aware of, or even because the person checking your ticket has gotten the restrictions wrong. And you might also be delayed for hours upon arrival waiting for temperature checks and related procedures and paperwork, or even get quarantined for up to two weeks. Be prepared for disruption to your travel plans, especially if traveling internationally.
If you are infected with COVID-19, you may be isolated until several consecutive tests for COVID-19 are negative, or until a certain number of days after symptoms have stopped. If you have been in close contact with someone infected with COVID-19, many countries will quarantine you for 14 days since the last exposure and monitor you for signs and symptoms. Some countries will also test you even if you don't have symptoms. The country you are travelling to may make use of "quarantine hotels" whereby incoming travellers coming from "high risk" COVID areas must serve their self-isolation period at a government-sanctioned facility (oftentimes, the traveller will be responsible for the costs of accommodation and they may have no option of which facility they wish to do it in). The criteria for classification into a "high risk" COVID area is obviously going to depend on the receiving country.
Domestic travel is generally less restricted than international travel although if authorities identify that the worst of the outbreak is concentrated in a few cities or regions, they may restrict domestic travel into and out of such areas. Depending on the level of transmission and vaccination, in some countries domestic travel is even safe and relatively unrestricted. If that's true where you are, consider this an opportunity to explore destinations in your own backyard that you might never have visited before. The lack of foreign tourists means that now may be your best opportunity to visit world-famous sights in your own country without the usual crowds - if they are open that is.
One response to the complications and restrictions has been the rise of "small travel", which is traveling to a nearby location and then treating that location as if it were a normal trip, by choosing places to eat, sights to see, or places to stay. It differs from a staycation or a day trip by normally involving an overnight stay. Instead of traveling to a distant area, however, small travelers might go no further than the next town.
Lockdowns and other internal restrictions
Some countries and regions, especially severely affected ones, have implemented emergency lockdowns and restrictions on people's movements and activities, even for those who haven't recently been abroad. These include the temporary reintroduction of some border controls, restrictions on travel within the country (for instance, mandatory registration or quarantine upon arrival in some states or provinces), closing or limiting service at restaurants and other establishments, banning large public events, and in the most severe cases prohibiting people from leaving their home except for essential purposes. Beyond government restrictions, individual establishments have shut their doors and cancelled events to try to reduce the spread of the virus.
In an attempt to contain domestic outbreak and track down infected patients, various countries have developed contact tracing mobile apps, such as China's Health Code and New Zealand's COVID Tracer. You should download and register (if necessary) for these apps before your travel. In some countries their use may still be mandatory, and using fake ones may attract criminal liability.
Penalties for violating restrictions vary by location: in some places they are not enforced much, but in others authorities take the rules very seriously and issue large fines along with imprisonment and deportation for violations.
With lots of flights cancelled, warnings issued, and restrictions imposed, flying in the time of coronavirus can be a challenge. Some routes are not possible. Others will require more inconvenient connections than usual—multiple stops and long waits between flights. In some cases that means more expensive tickets.
Build in extra time for your connections, especially if transferring from an international flight to a domestic flight and especially if your itinerary involves a country that has stringent restrictions. Screenings, temperature checks, extra paperwork, and the associated waiting around can add minutes or hours before you're allowed to continue on your journey.
Connecting flights can be a problem in some cases. Although international-international transit passengers generally face fewer restrictions than arriving passengers, the risk of getting stuck in the connection city is higher than usual right now, due to delays for screening and testing as well as extensive cancellations. Connecting in an affected area may lead to entry restrictions later on, and if you've been in an affected area recently some countries won't even let you change planes. On certain itineraries there is a risk of getting quarantined somewhere along the way. So book a non-stop flight if you can, and if not, think carefully about where to connect. Avoid short layovers.
Once your ticket is booked, monitor the reservation in case your flight gets cancelled. Airlines are drastically cutting back flights, and flight cancellations have become common. If your flight is cancelled, contact your airline or travel agency. Depending on the route, another flight the same day may not be available, or not in the same price range, so you may have to reschedule for a different day. No small number of travellers have been stranded by widespread cancellations.
In uncertain times, plans can change. Consider buying refundable tickets.
Many embassies and consulates have evacuated nonessential staff, and some have shut down operations completely. Emergency assistance should still be available, though it's possible you may have to contact a further-away consulate if your local one has shut down. If you have been stranded due to the pandemic, your nearest consulate may be able to help you find a flight home, arrange an emergency loan so you can buy a ticket, or provide an emergency passport. At the very least they can keep you informed about the local situation and notify you about recently introduced travel requirements and restrictions.
Ordinary consular services such as visa and passport processing may be suspended or restricted to urgent need, depending on the location and the consulate.
If you are traveling or living abroad, now is an excellent time to register with your embassy or consulate for updates on restrictions, flight availability, and other developments.
When it comes to mask wearing and other precautions, legal requirements and official advice don't tell the full story. Different countries and regions have developed different expectations around when masks should be worn, which sometimes go beyond what's officially required. When you arrive in your destination, pay attention to see if other people are wearing masks in places where you wouldn't have thought it was necessary. If they are, follow their lead.
Refrain from using terminology that connects the disease with countries, cities, ethnicities etc. Such terminology is widely used in some circles, perhaps even officially, but it strengthens prejudices and can be perceived as racist. Instead, use location-neutral terms, such as "COVID-19", "coronavirus", or just "the virus" or "the pandemic".
This is the same for SARS-CoV-2's variants, where people may be offended by linking COVID-19 variants to their homeland. They have now been given location-neutral names which include: Alpha for the variant first found in the UK, Beta for the one found in South Africa, Gamma for the one found in Brazil, Delta for the one found in India, and Lambda for the one found in Peru. Omicron, found in late November 2021, resulted in tightened restrictions before anything really was known about its behavior.
Many areas that have ordered restaurants to be closed to dine-in customers allow them to serve takeaway and delivery customers. In countries where tipping is common such as the United States and Canada, tip more generously than usual, due to the heightened risk for delivery personnel, and tip electronically when possible to avoid possible contagion. Where dine-in service is allowed, keep your mask on when the server is at your table, and wait for them to walk away before you take the mask off and start eating.
Particularly in developing countries, enforcement of curfew, lockdown or stay-at-home orders may be far from gentle. Comply with these orders, and avoid crowds in public.
COVID-19 policy can be contentious and attract protesters opposed to mask mandates or other government measures. Such protests should be avoided, partly because either the protesters or the police may turn violent. Also, protesters rarely use personal preventive measures or maintain safe distance, making these protests hot spots of COVID-19 transmission.
As a result of the pandemic, xenophobia has risen in many countries, primarily but not exclusively targeting people perceived to be Chinese. There has been a worldwide spike in racist incidents targeting people of East Asian origin, including physical assaults, and including in major cities such as New York, London and San Francisco.
Levels of xenophobia have also risen in Asia, with some restaurants, hotels, and other businesses in China, Japan, and India refusing service to foreign customers. In China, discrimination is particularly severe against black people, with some having been evicted by their landlords.
Government travel advisories
Sources for further information on the COVID-19 pandemic include:
- World Health Organization
- The US government Centers for Disease Control and Prevention
- European Centre for Disease Prevention and Control (weekly updates)
- Partial list of entry restrictions from IATA
If you're abroad, your country's embassy is also a source of information about the local situation and travel restrictions. The embassy website may have a dedicated COVID-19 page, and now is an excellent time to register with the embassy for email updates. In particular, a lot of British and American embassies are maintaining detailed information in English about local restrictions, which might be worth checking even if you're not an American or British citizen.
A variety of misinformation and conspiracy theories about the virus are being promoted online and even by some government officials, so be careful which sources you check for information. Ensure that all information and advice you receive has been backed by reputable doctors and scientists.
In a crisis, it's natural to want to keep following the latest updates, but it may be better for your mental health to moderate the amount of news that you look at. If you normally watch the news twice per day then stick to this schedule and do something else, rather than having the 24-hour news on continuously.