Last updated February 20, 2020.
- Coronavirus disease 2019 (COVID-19) is a newly identified viral disease in China that results in respiratory illness (including pneumonia) and is acquired via inhalation of airborne respiratory droplets from an infected person, direct contact with contaminated surfaces, or direct contact with an animal source (possibly pangolins).
- Risk is generally low for travelers going to China but may be increased in persons exposed to ill-appearing persons in affected areas or those using health care facilities in affected areas (especially for persons with underlying medical conditions). The situation has been declared a Public Health Emergency of International Concern and is evolving daily; a travel medicine specialist should be consulted immediately before the actual trip.
- Symptoms commonly include fever, cough, shortness of breath, and difficulty breathing.
- Consequences of infection include severe pneumonia and possibly death.
- Prevention includes observing respiratory hygiene (cough and sneeze etiquette), hand hygiene (frequent, thorough handwashing), and social distancing (maintaining a distance of 2 m [6 ft] from ill-appearing persons) and avoiding direct or indirect contact with animals (live or dead).
- No vaccine, preventive drugs, or treatments are available. Oseltamivir (Tamiflu) and acyclovir are ineffective. Current influenza vaccination is recommended to decrease the risk of simple influenza being mistaken for COVID-19 upon return.
- Most countries are advising deferral of either nonessential travel or all travel to China; a number of countries have published entry travel 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 Wuhan, Hubei Province, China in December 2019. 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 is centered in Hubei Province, but cases (and community-based transmission) are occurring throughout China. More than 74,000 cases (including > 2,100 deaths) have been reported as of mid-February 2020, and the outbreak is unlikely to peak for many months. A large one-day increase in China cases reported in mid-February was a result of new diagnostic criteria being used in China. More than 200 imported cases in more than 26 countries have been reported since early January 2020. More than 800 cases (including > 600 cases on cruise ships) due to transmission outside of China have occurred; most countries receiving imported cases have been successfully isolating infected persons and preventing further onward transmission. The World Health Organization has declared the outbreak to be a Public Health Emergency of International Concern and assesses the risk to be very high in China, high at the regional level, and high at the global level.
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).
Risk exists throughout China, mainly in central and eastern provinces, especially Hubei Province. Negligible risk exists in other countries with either imported cases or limited local transmission; however, risk is slightly higher in Hong Kong, Japan, Singapore, and South Korea, where several case clusters have been reported.
Virus transmission occurs via inhalation of airborne respiratory droplets from an infected person, direct contact with contaminated surfaces, or direct or indirect contact with an animal source (not yet identified). The frequency of transmission from symptom-free individuals infected with SARS-CoV-2 to others is unknown, but several apparent instances have been documented. Human-to-human transmission has been ongoing since December 2019 in China and has also occurred elsewhere.
The survival rate of SARS-CoV-2 on surfaces or in the environment is currently unknown. In general, the survivability of coronaviruses on surfaces is significant, usually 1 to 6 days (longest on plastic); the risk of spread is very low from items shipped at ambient temperatures over several days. No evidence exists of SARS 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 for now. 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 15 mL (1 tablespoon) of bleach to 1 L (1 quart) of water; for a larger supply, add 60 mL (2 oz) of bleach to 4 L (1 gallon) of water.
Risk is generally low for travelers but may be increased in the following cases:
- Travel to areas where cases have been reported
- 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)
The situation is evolving daily, and a travel medicine specialist should be consulted immediately before the actual trip.
Symptoms commonly develop within 2 to 7 days (5 days typically, but up to 14 days) after infection and include fever, cough, shortness of breath, and difficulty breathing. Runny nose, sneezing, and sore throat are uncommon.
Consequences of Infection
COVID-19 presents with pneumonia in essentially all cases. Severe illness, more likely in persons with underlying medicals conditions or older adults, occurs in about 20% of cases. Accurate death rates are impossible to calculate based on available information.
Need for Medical Assistance
Travelers who have been exposed to or who develop symptoms of COVID-19 upon return from China or who have had any contact with a known case in another affected country (Australia, Belgium, Canada, Egypt, France, Germany, Hong Kong, India, Italy, Iran, Japan, Macau, Malaysia, Philippines, Singapore, South Korea, Spain [Mallorca Island], Taiwan, Thailand, U.K., U.S., United Arab Emirates, Vietnam) should observe respiratory hygiene (cough and sneeze etiquette), hand hygiene (frequent, thorough handwashing), and social distancing (maintaining a distance of 2 m [6 ft] from ill-appearing persons), wear a face mask, and seek immediate medical attention, informing the provider of their travel history.
No vaccine or known treatment exists. 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.
Travel to China
Travelers going to affected areas should:
- Observe respiratory hygiene (cough and sneeze etiquette), hand hygiene (frequent, thorough handwashing), and social distancing (maintaining a distance of 2 m [6 ft] from ill-appearing persons).
- 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
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 greater 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 should not return to work until they are free of fever and other symptoms for at least 24 hours without the use of fever-reducing or other symptom-altering medications (e.g., cough suppressants). Should an outbreak of COVID-19 occur in the U.S., large-scale absenteeism is possible.
Employees, Students, Visitors, All Others Coming from China
Arrivals who develop fever or respiratory symptoms within 14 days of travel to China should self-isolate; observe respiratory hygiene, hand hygiene, and social distancing; wear a mask; and contact public health authorities (or telephone ahead before presenting to a hospital).
The extent of transmission from symptom-free individuals infected with SARS-CoV-2 to others is unknown but several apparent instances have been documented. Influenza viruses can be transmitted 1 to 2 days prior to symptom onset. SARS-CoV did not transmit until 4 days after symptom onset, which led to its eradication because all contacts with fever could be promptly identified and isolated.
In general, employers and schools in the U.S. and many Asian countries are excluding from the workplace or school all employees and students who returned from anywhere in China in the past 14 days. Symptom-free individuals arriving from Hubei Province, China (high-risk exposure) will be quarantined and subject to daily active monitoring (communication with public health authorities). Symptom-free individuals arriving from other locations in China (medium-risk exposure) should self-quarantine (remain at home or in a comparable setting) if possible and self-monitor (take temperature 2 times per day) and avoid congregate settings, limit public activities, and remain out of public places where close contact may occur. Several countries have specific national requirements for all returnees from China to self-quarantine for 14 days.
Symptom-free individuals with a low-risk exposure outside of China (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 individuals as well.
Based on advance information and employee or visitor medical screening, additional preventive measures may be required (e.g., increased ventilation, larger meeting rooms with more personal space per participant, disinfection of work areas and lavatories, and provision of alcohol wipes). The public use of masks by symptom-free persons is not beneficial.
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 China 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 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 China. Recommendations range from avoiding nonessential travel to anywhere in China to avoiding all travel to Wuhan, Hubei Province, or all of China.
Entry screening (e.g., questionnaires, fever screening, thermal scanning, or visual inspection) has been implemented at international ports of entry in almost all countries. Anyone with fever and respiratory symptoms who has been in China in the past 14 days will be detained and isolated. Anyone without symptoms but with travel to China in the past 14 days may be placed in quarantine or self-quarantine depending on where in China the exposures may have taken place.