Over the past weeks, health officials around the globe traced and advised suspected contacts of people with the coronavirus disease (COVID-19) to isolate themselves for 14 days, the incubation period of the disease.
From there, they would report if they developed the symptoms of the illness, including fever, dry cough, and difficulty of breathing. If they did not manifest any of the symptoms after the two-week quarantine period, they are free to go.
Now, health officials have warned that the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may have a more extended incubation period than previously thought.
The puzzling and surprising new development in the disease’s incubation period has sparked fears that the 14-day quarantine period is not enough to contain the spread of the virus. Moreover, many individuals who were out of the quarantine period may still harbor the virus and can lead to more infections.
Coronavirus incubation period could be 27 day. Image Credit: Mongkolchon Akesin / Shutterstock
Longer incubation period
Health officials have imposed the 14-day quarantine periods to most individuals who had close contact with a confirmed case or those who were repatriated from Wuhan City in Hubei province.
A man in China, who had close contact with a family member who tested positive of the coronavirus, developed symptoms after 27 days of exposure. The 70-year-old man in Hubei Province was infected with the coronavirus but did not show any signs until nearly one month later. Identified as Jiang, his family name, the patient drove his car back on Jan. 24 to Shennongjia, in northwestern Hubei, from eastern Ezhou, where he had close contact with his sister, who had contracted the virus.
His symptoms appeared much later than expected, having fever on Feb. 20, and tested positive for coronavirus a day later.
A severe blow to quarantine efforts
Health officials, governments, health agencies, and the World Health Organization is working hard to contain the deadly virus that has killed over 2,600 people in just two months and infecting nearly 80,000 people.
All the quarantine efforts lasted for 14 days, to ensure that the person will not have close contact with other people while he or she is infected. This way, health officials can limit human-to-human transmission and effectively trace connections of those who tested positive for COVID-19. After 14 days, and the patients have shown no symptoms, they are free to go home. This routine went on for weeks now, but the new development in the disease’s incubation period is a severe blow to efforts made by health agencies across the globe.
A more extended incubation period would mean it can be much more challenging to fight the disease. It will become tough to prevent the spread of the virus, since many patients are still infectious, and they are out of their quarantine period.
This can explain the sudden spike of coronavirus cases in other countries, such as South Korea, Italy, and Iran. South Korea has reported 763 cases and seven deaths, a sudden spike from just more than the 30 cases in the country four days ago. The outbreak in South Korea has been traced to a religious group in the Daegu area.
Italy has reported 155 cases, and Iran has 43 cases. The outbreak has reached 30 countries, prompting governments to impose travel bans and high alerts on addressing the problem.
At present, 24,963 people have recovered from the disease. They are still being observed to determine the virus can still be active despite the patient recovering from the illness.
Even without symptoms
Previous data has shown that the coronavirus can be spread even if a person has no symptoms. A 20-year-old woman in Wuhan, the city where the outbreak started, traveled to Anyan on Jan. 10, and after three days, she went with five family members to visit a patient who did not have the coronavirus.
One of the woman’s family members had a fever and sore throat on Jan. 17. In the coming week, four other family members had a fever, and they all tested positive for coronavirus. The woman, who was in close contact with all family members, was initially tested negative for the coronavirus. The CT scan of her lungs was normal, but after one day, her test came out positive. The woman did not manifest any symptoms, and by Feb. 11, she had no fever or sore throat.
The doctors who handled the case said that the woman’s incubation period was 19 days, longer than the previous 14 days. However, new information shows it could be as long as 27 days.
The symptoms of Covid-19 include fever, dry cough, and shortness of breath. In severe cases, it can lead to breathing difficulties and acute respiratory distress.
Dong, E., Du, H., and Gardner, L. (2020). An interactive web-based dashboard to track COVID-19 in real time. The Lancet. https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(20)30120-1/fulltext
U.S. Centers for Disease Control and Prevention (CDC). (2020). Coronavirus Disease 2019 (COVID-19). https://www.cdc.gov/coronavirus/2019-ncov/about/symptoms.html
Coronavirus COVID-19 Global Cases by Johns Hopkins CSSE - https://gisanddata.maps.arcgis.com/apps/opsdashboard/index.html#/bda7594740fd40299423467b48e9ecf6