COVID-19: Wading through the darkness

It has been hard to move for headlines on the new Corona Virus over the last couple of weeks, and it’s easy to see why. The infection now poses the greatest challenge for public health for a generation and is highlighting the shortcomings of global health services, especially as – inconveniently – viruses don’t really care about borders or politics.

So, underneath the media hysteria, politician’s statements, economic panic and public confusion, what does the science have to say about the virus? Well, obviously, research and publications take time to form but some useful reviews are now coming from China and beyond. As the region of origin, Chinese scientists have had the most time to study how the virus behaves. I’m going to focus on three publications, which will hopefully shed light

• Coronavirus 2019-nCoV: A brief perspective from the front line – Qingmei Han et al. (2020) Journal of Infection

This paper describes the virus really well.

• Clinical characteristics of 50466 hospitalized patients with 2019-nCoV infection – Pengfei Sun et al. (2020) Journal of Medical Virology

These researchers pooled information from 10 studies to cover the symptoms of as many patients as possible.

• Coronavirus Disease 2019 (COVID-19) and Pregnancy: What obstetricians need to know – Sonja Rasmussen et al. (2020) American Journal of Obstetrics and Gynecology

An interesting paper from a personal perspective as I am 8 months pregnant. There has basically been no information forthcoming on the risk to pregnant women, or their babies.

What do these papers tell us?

Useful background info:

Corona viruses are a family of viruses. The current outbreak is being driven by the 7^th member of the family found to cause disease in humans (COVID-19). It has been traced to a seafood market in Wuhan, although genetic testing suggests it may have originated from a bat. It is likely that another species, probably illegally traded pangolin at the market (sigh), was the intermediate vehicle to human infection. Other members of the corona virus family include SARS (Severe Acute Respiratory Syndrome) and MERS (Middle Ease Respiratory Syndrome), which previously hit the headlines with their own outbreaks in 2002 and 2012 respectively.

Useful info for those avoiding COVID-19:

• Survival time in the air is about 2 hours
• Incubation period (the time it takes between picking up the virus and having first symptoms) is 4-8 days.
• All age groups can become infected, but elderly people with other diseases (diabetes, high blood pressure, heart conditions etc.) are more likely to experience severe illness.
• Those people who are in the incubation period of the infection are the main sources of spreading the infection. This presents a big challenge as people who are not yet feeling ill are already passing the virus on.
• Coughs and sneezes (i.e., sources of droplets from the airways) are the main routes for the virus to spread, although poop and touching the eye area with a contaminated hand cannot be ruled out.

Symptoms (percentages based on Chinese data only)

• Fever (experienced in 89.1% of patients)
• Fatigue and body aches (experienced in 42.5% of patients)
• Dry cough (experienced in 72.2% of patients)
• Runny nose, sore throat and diarrhea (experienced in fewer patients).
• The severe illness causes pneumonia (experienced in 18.1% of patients), which has been the cause of most of the deaths (up to 4.3% of patients).

Testing and treatment

• Some patients had several negative tests for the virus before showing a positive.
• There are currently no treatments, although these are now being researched and tested. There are several anti-viral medications against other diseases that could be modified to target COVID-19.
• People who develop severe pneumonia are usually treated with steroids.
• Antibiotics will not help as they are not effective against viruses.

And for pregnant women?

• Researchers are having to look back at SARS and MERS for clues on how COVID-19 might affect pregnant women and their babies.
• The outcomes in these past infections differed depending on how far the pregnancy had progressed before contracting the virus. It is likely to be the same for COVID-19.
• Pregnant women are predicted to have the same susceptibility to the virus as the non-pregnant population.
• Symptoms of the virus are predicted to be the same as the non-pregnant population.
• It is not clear whether pregnant women are more likely to experience severe disease.
• It is possible that infection during pregnancy will cause distress to the baby. Cases so far have shown an increase in preterm caesarean section deliveries.
• If you are pregnant and think you have COVID-19, it is imperative to seek medical advice and to undergo monitoring.
• SARS and MERS were not passed from mother to baby in the womb, however this has not been ruled out for COVID-19.
• It is possible (although not demonstrated) that COVID-19 could be transmitted through breast milk.

All this is very interesting, but how can the virus be controlled and stopped? The short answer seems to be that it can’t. According to the WHO, each person who contracts the virus will spread it to between 2 and 3 people, which is why the rate of infection seems to be growing and growing. Now, public health and governments are faced with the challenge of what to do. Although different countries implementing different strategies may seem nonsensical, there may be more thought to it than meets the eye. Each population is different. The advice given may reflect the population density, proportion of elderly and healthcare capacity, for example. This varies from country to country. Top decision makers may also be gambling on the development of immunity. If this is the case, controlled spread of the virus is vital. As healthy individuals are exposed, they could develop their own immunity to the disease, meaning that it will not be transmitted as readily. This will then help to protect the more vulnerable groups from contracting it. Herd immunity, as it is also known, forms part of the success of vaccination programs, and could help with pandemic viral spread too. The key is to keep the level of infection at a level that does not overwhelm healthcare capacity.

Overall, I hope we can see that COVID-19 is not “just another flu”. You may be young, fit and healthy but being complacent may just accidentally kill your granny. This is one of the few examples where community behaviour really makes a difference so keep washing your hands!

Image available from NIH NIAID on Flickr, protected under a CC licence