Silent spreaders of COVID-19: People without symptoms

Sir: Five months since the coronavirus disease (COVID-19) was first reported in China, there are still many unknowns about the disease. However, what is known is that of all the people that contract the virus, the majority will have mild to moderate symptoms and recover after a period of isolation. Others will have more serious and life-threatening symptoms with complications. These are the patients that require intensive care and may need to be put on ventilators if they have Acute Respiratory Distress Syndrome (ARDS). 

According to data released by the Nigeria Centre for Disease Control, the majority of people in Nigeria have mild to moderate symptoms. It can be easy to wonder why the heightened concern about the virus then? The concern stems from the fact that there are people who have no evident symptoms of the virus such as cough, fever, and difficulty in breathing. They are either pre-symptomatic (symptoms of the virus have not yet developed, but they can start transmitting the virus 24 to 48 hours before they start showing symptoms) or asymptomatic (they will not develop symptoms but can still the transmit the virus).

Whether a person is showing symptoms or not, once they have been infected with the virus, they can also infect others. This can happen if a person becomes exposed to asymptomatic, asymptomatic or pre-symptomatic person through respiratory droplets from coughing or sneezing.

In addition, the transmission of the virus can occur through indirect contact, from surfaces in the immediate environment or frequently touched objects an infected person may have come in contact with e.g. a doorknob, light switches or countertops. Therefore, in any setting, whether home or work, it is imperative that frequently touched surfaces are cleaned and disinfected daily.

Asymptomatic people are also less likely to be diagnosed with COVID-19, as they will not meet the standard case definition for testing, hampering efforts being made to limit the transmission of the virus. This highlights the advice from the Federal Ministry of Health that face masks should always be worn in public, as an additional precautionary measure particularly where physical distancing may be a challenge. Active case finding in high-density communities has been a way of identifying, tracing, testing and isolating asymptomatic cases.

A security man stands at the main gate of Computer Village, the largest Information and Communications Technology accessories market in African continent, to prevent access to the market in compliance with the extended lockdown by the government as measures to curb the spread of COVID 19 coronavirus in Lagos, on May 18, 2020. – Nigeria’s government on Monday extended a coronavirus lockdown on the northern region of Kano after it became a hotspot for new infections.†The head of the country’s coronavirus taskforce, Boss Mustapha, said the lockdown on the economic hub — which includes Nigeria’s second-biggest city — would be prolonged for two weeks. (Photo by PIUS UTOMI EKPEI / AFP)

As many asymptomatic people do not feel “ill”, when they are tested and diagnosed with COVID-19, they may question their diagnosis or resist being put into an isolation centre. However, this is necessary if the Nigeria government is to effectively control the spread of the virus. As a society, we have a role to play and should #TakeResponsibility in protecting ourselves from catching the virus, as well as encouraging others to do the same. Vulnerable persons can also stay protected by ensuring they avoid non-essential outings and visitors as well as aspractice the necessary public health preventive measures.

• Mary Ayodele is a public health and safety counsellor.