Last updated March 26, 2020.
- Coronavirus disease 2019 (COVID-19), a newly identified viral disease that originated in China, has now spread worldwide, with the number of cases reported outside of China exceeding the number of cases reported in China; Europe and the U.S. are currently most affected. COVID-19 results in respiratory illness (including pneumonia) and is acquired via inhalation of airborne respiratory droplets from an infected person or direct contact with contaminated surfaces.
- Risk is present for persons in countries with ongoing community transmission (no obvious exposure to ill-appearing persons) or those using health care facilities in affected areas (especially for older persons and those with underlying medical conditions). Risk should be assumed present in all countries of the world and is higher with exposure to ill-appearing persons. The situation has been declared a global pandemic by the World Health Organization (WHO) and is evolving daily; a travel medicine specialist should be consulted immediately before an actual trip.
- Symptoms commonly include fever, cough, shortness of breath, and difficulty breathing.
- Consequences of infection include severe pneumonia, respiratory failure, and, possibly, death.
- Prevention includes observing respiratory hygiene (cough and sneeze etiquette), hand hygiene (frequent, thorough handwashing with soap and water for 20 seconds [or using a hand sanitizer containing 60% alcohol]), and social distancing (remaining out of congregate settings, avoiding mass gatherings and public transportation, and maintaining a distance of 2 m [6 ft] from others).
- No vaccine, preventive drugs, or treatments are available, although some existing medications (including hydroxychloroquine) have shown promise for treatment of ill persons. Oseltamivir (Tamiflu) and acyclovir are ineffective. Do not take any treatment medications unless prescribed by a provider. Face masks are not effective in preventing infection in public places. Fraudulent COVID-19 treatments and home diagnosis kits come in many varieties, including dietary supplements, teas, essential oils, tinctures, and colloidal silver. Current influenza vaccination (and pneumococcal vaccination if otherwise indicated) is recommended to decrease the risk of simple influenza being mistaken for COVID-19 upon return.
- Most countries are advising deferral of either nonessential international travel or all travel, even domestically. A number of countries have published travel entry restrictions, and some have medical clearance requirements.
- Entry screening has been implemented at international ports of entry in almost all countries; persons with history of travel to a risk location will be detained and isolated or quarantined based on symptom status.
COVID-19, a newly identified acute disease that causes respiratory illness (mainly pneumonia), was first detected in China in December 2019 and has since spread to all countries worldwide, with the number of cases reported outside of China exceeding the number of cases reported in China. The causative coronavirus (SARS-CoV-2) is closely related to the severe acute respiratory syndrome coronavirus (SARS-CoV) that caused SARS in 2002-03. The outbreak outside of China consists of more than 400,000 cases (including more than 19,000 deaths as of late March); Europe and the U.S. are currently most affected. The global outbreak is unlikely to peak for many weeks and is likely to cause significant risk and disruption for many months. WHO has declared the outbreak to be a global pandemic, the worst possible scenario.
Limited information is available on the severity and period of transmissibility of this virus. Transmission occurs via inhalation of airborne respiratory droplets from an infected person, direct or indirect contact with contaminated surfaces, or via direct contact with an animal source (possibly pangolins). Transmission from persons that do not appear ill may occur, although most transmission is from household members and other close contacts.
Significant risk exists in every country of the world, especially in Europe and the U.S. at present. The outbreak appears presently controlled and almost over in China. Future waves of transmission are possible.
Virus transmission occurs via inhalation of airborne respiratory droplets from an infected person or direct contact with contaminated surfaces. Transmission from persons that do not appear ill may occur, although most transmission is from household members and other close contacts.
The survival rate of SARS-CoV-2 is about 1 to 6 days at room temperature, with specific survival rates of 72 hours on plastic and stainless steel, 24 hours on cardboard, and 4 hours on copper. The risk of spread is very low from items shipped at ambient temperatures over several days. No evidence exists of SARS-CoV-2 transmission associated with imported goods; no associated cases have been reported in the U.S.
Disinfection processes that are effective for other coronaviruses should be followed. Clean daily all "high-touch" surfaces, such as counters, tabletops, doorknobs, bathroom fixtures, toilets, phones, keyboards, tables, and bedside tables. Also, clean any surfaces that may have blood, bodily fluids, and/or secretions or excretions on them. Use a diluted bleach solution or a household disinfectant with a label that says "EPA-approved." To make a bleach solution, add 20 mL (4 teaspoons) of bleach to 1 L (1 quart) of water; for a larger supply, add 75 mL (5 tablespoons) of bleach to 4 L (1 gallon) of water.
Risk is significant for travelers going to all countries but may be increased in the following cases:
- Close contact with ill-appearing persons or persons diagnosed with COVID-19 (especially high risk)
- Inpatient or outpatient visits to health care facilities in an affected area
- Direct or indirect contact with animals (live or dead), animal markets, or products that come from animals (such as improperly cooked meat)
- Underlying medical conditions (chronic diseases or weakened immune system)
Persons who have underlying high blood pressure, heart disease, or heart failure should not stop taking blood pressure medications classified as angiotensin-converting–enzyme (ACE) inhibitors (e.g., lisinopril, captopril) or angiotensin-receptor blockers (ARBs; e.g., telmisartan, valsartan).
The situation is evolving daily, and a travel medicine specialist should be consulted immediately before an actual trip.
Symptoms commonly develop within 2 to 7 days (typically 5 days, but up to 14 days) after infection and include fever, cough, shortness of breath, and difficulty breathing. Loss of the sense of smell and taste have been reported. Runny nose, sneezing, and sore throat are uncommon. In some patients, symptoms are mild the first week and shortness of breath or pneumonia do not begin until the second week.
No scientific evidence exists linking ibuprofen and a worsening of COVID-19, and ibuprofen may be used as needed. Persons on certain blood pressure medications (as noted above) should continue those medications.
Consequences of Infection
COVID-19 presents with pneumonia in essentially all cases. Severe illness, more likely in persons with underlying medical conditions or older adults, occurs in about 20% of cases. Death rates vary from 1% in large populations to up to 10% in vulnerable populations (persons with underlying medical conditions).
Need for Medical Assistance
Travelers who have been exposed to or who develop symptoms of COVID-19 upon return from any travel or who have had any contact with a known case should observe respiratory hygiene (cough and sneeze etiquette), hand hygiene (frequent, thorough handwashing with soap and water for 20 seconds [or using a hand sanitizer containing 60% alcohol]), and social distancing (remaining out of congregate settings [crowded places such as shopping centers, movie theaters, and stadiums], avoiding mass gatherings and public transportation, and maintaining a distance of 2 m [6 ft] from others), wear a face mask, and seek immediate medical attention, informing the provider of their travel history before presenting to a clinic or hospital.
No known treatment exists, but a few existing medications (including hydroxychloroquine) have shown promise; discuss with a provider and do not take any treatment medications unless prescribed or recommended by a provider. Usual antiviral drugs such as oseltamivir (Tamiflu) and acyclovir are ineffective; several antivirals are awaiting approval for use in China, and 1 unlicensed antiviral is available from U.S. CDC. Care is supportive to relieve symptoms or to support vital organ functions in severe cases. Persons who develop any shortness of breath should contact a medical provider immediately.
Fraudulent COVID-19 treatments and home diagnostic tests come in many varieties, including dietary supplements, teas, essential oils, tinctures, and colloidal silver. These products are not proven safe or effective and may delay proper diagnosis and treatment of COVID-19.
Travel to Any Country
Travelers going to affected areas should:
- Observe respiratory hygiene (cough and sneeze etiquette), hand hygiene (frequent, thorough handwashing with soap and water for 20 seconds [or using a hand sanitizer containing 60% alcohol]), and social distancing (remaining out of congregate settings [crowded places such as shopping centers, movie theaters, and stadiums], avoiding mass gatherings and public transportation, and maintaining a distance of 2 m [6 ft] from others).
- Avoid close contact with persons diagnosed with COVID-19 (especially high risk).
- Avoid direct or indirect contact with animals (live or dead), animal markets, or products that come from animals (such as improperly cooked meat).
- Avoid busy medical settings for minor medical problems. The quality of infection-control standards at medical facilities in Wuhan or other affected areas is uncertain.
- Ensure influenza vaccination is current to decrease the risk of simple influenza being mistaken for COVID-19 upon return.
In the Workplace and Schools
To help prevent workplace exposure to acute respiratory illnesses, including COVID-19, employers should actively encourage (through generous leave policies) employees with fever (37.8°C [100.4°F] or higher using an oral thermometer), signs of fever, or symptoms of respiratory illness to remain at home, to observe hand hygiene and social distancing if possible, and to avoid sharing household items. Employees who become ill at work should be immediately isolated from other employees and sent home. Employee education on the aforementioned measures should be aggressive. Worksite hygiene measures and worksite disinfection should be active and continuous.
Employees, including health care workers (HCWs), with confirmed or suspected COVID-19 should not return to work until they test negative for COVID-19 (at least 2 negative consecutive specimens collected ≥ 24 hours apart) and are free of fever and other symptoms for ≥ 72 hours without the use of fever-reducing or other symptom-altering medications (e.g., cough suppressants) and ≥ 7 days have passed since symptom onset. Symptomatic persons who meet testing criteria (including older persons and those with underlying medical conditions) but who have a negative test may return to work once asymptomatic (as noted previously) for ≥ 72 hours. Symptomatic persons who do not meet local COVID-19 testing criteria may return to work once symptom-free for at least 24 hours, similar to the guidelines for influenza. In cases where employers nevertheless consider an employee to be a high risk of being positive for some reason, the employer may choose to require either a negative COVID-19 test result or, if testing is not available or test status is not known, that ≥ 7 days have passed since symptom onset and the employee has remained symptom free for ≥ 72 hours before allowing a return to work. Symptom-free persons with a positive test may return to work once ≥ 7 days have passed from the date of the positive test and they have remained symptom free. HCWs returning to work should wear a face mask until all symptoms are completely resolved or until 14 days have passed since symptom onset, whichever is longer; they should also avoid contact with patients with severely weakened immune systems until 14 days have passed since symptom onset.
Employees, Students, Visitors, All Others Coming from China or Countries with Community Transmission
Arrivals who develop fever or respiratory symptoms within 14 days of travel to countries with community transmission should self-isolate; observe respiratory hygiene, hand hygiene, and social distancing; wear a face mask; and contact public health authorities (or telephone ahead before presenting to a hospital).
In general, employers and schools in many countries are excluding from the workplace or school all employees and students who have returned from COVID-19–affected countries in the past 14 days. Symptom-free persons arriving from countries with widespread, ongoing community transmission (medium-risk exposure) should self-quarantine (remain at home or in a comparable setting) if possible and self-observe (remain alert for symptoms) or self-monitor (take a temperature reading 2 times per day), and observe social distancing. Many countries have specific national requirements for all returnees from COVID-19–affected countries to self-quarantine for 14 days.
Symptom-free persons with a low-risk exposure (same indoor environment with a symptomatic COVID-19 case but without close contact) should self-observe for 14 days after their last potential exposure, but no movement restrictions are recommended; however, an employer may choose to apply the aforementioned stricter recommendations to these persons as well.
Household members of a suspected case should observe hand hygiene and social distancing if possible and should avoid sharing household items. Such persons should self-monitor, and employers may consider various options, including exclusion from the workplace until 14 days after the last possible day of infectiousness for a suspected case. Household members of a symptom-free person in self-quarantine following a return from a COVID-19–affected country are not considered to be at-risk contacts but should consider following the aforementioned recommendations. They may continue their daily activities (e.g., work or school) while continually monitoring their health and seeking medical attention if symptoms develop. However, businesses may conservatively opt to implement restrictions on a case-by-case basis.
Caregivers of a suspected or confirmed case should take additional precautions to include the use of disposable gloves, gowns, and face masks and the proper disposal of these items.
Travel Restrictions and Advisories
A number of countries have published travel restrictions or recommendations. Different levels of travel restrictions are in effect and include closed land borders, closed airports, medical clearance required for entry, and internal restrictions within countries. Recommendations range from avoiding nonessential travel to avoiding all travel to all countries.
Entry screening (e.g., questionnaires, fever screening, thermal scanning, or visual inspection) has been implemented at international ports of entry in almost all countries. Any traveler with fever and respiratory symptoms who has been in any country may be detained and placed in isolation or self-isolation depending on where the exposures may have taken place.