The race to stop COVID-19

Download the full print version of the infographic here.

In context 

Compared with some outbreaks of novel respiratory disease, the death rate for coronavirus disease 2019 (COVID-19) is currently low. This could reduce further as the global outbreak progresses and milder cases are detected. Pandemic (H1N1) 2009 influenza was estimated to infect 1.6 billion people, with a death rate of 1 in 5,000 (0.02%); seasonal flu has a similar death rate, but infects up to 4 billion people each flu season.

Global takeover

Symptoms and transmission

• Common symptoms*: fever (98.6%); weakness (69.6%); cough (59.4%); muscle pains (34.8%); difficulties breathing (31.2%);
• Less common symptoms*: diarrhoea (10.1%); nausea and vomiting (10.1%); dizziness (9.4%); headaches (6.5%); stomach pain (2.2%);
• Incubation period: 0–14 days;
• Severity: data from 44,000 cases of COVID-19 in China suggest that 80.9% of cases are mild, 13.8% are severe and 4.7% are critical. Severe cases are more prevalent in older people and those with an existing long-term condition, such as cardiovascular disease, diabetes, respiratory disease or hypertension;
• Transmission: person-to-person spread between close contacts (up to 1.8 metres) through respiratory droplets;
• Diagnosis: COVID-19 is suspected based on clinical symptoms. Cases are only confirmed when there is a positive laboratory test;
• Treatment: treatment of COVID-19 is symptomatic, such as providing oxygen. Medicines specifically licensed for COVID-19 are not currently available, but clinical trials of several antiviral drugs are being conducted in China.

*Percentages are taken from a case series of 138 consecutive hospitalised patients in China.

Vaccine development

There are five main approaches being taken to develop a vaccine against SARS-CoV-2, with several biotechnology companies, academic organisations and pharmaceutical companies employing different technologies in the race to bring their vaccine candidate to clinical trials. The World Health Organization hopes that a vaccine will be available by October 2021.  

1. Viral vector vaccine: 

• Organisations working on vaccine: 
  Johnson & Johnson; Geovax Labs and BravoVax; University of Oxford and Advent Srl; Tonix Pharmaceuticals and Southern Research; Altimmune; Greffex; Vaxart; CanSino Biologics; Zydus Cadila; Institute Pasteur 

• Estimated date of first human trials:  June 2020

2. DNA vaccine:

• Organisations working on vaccine: 
  
  Inovio Pharmaceuticals with Beijing Advaccine Biotechnology; Applied DNA Sciences, Takis Biotech and Evvivax;  Zydus Cadila

• Estimated date of first human trials:  April 2020

3. RNA vaccine:

• Organisations working on vaccine:
  
  CureVac; Moderna and US National Institute of Allergy and Infectious Diseases; Stermirna Therapeutics, Tongji University and Chinese Center for Disease Control and Prevention; Imperial College London

• Date of first human trials: March 2020

4. Live-attenuated vaccine: 

• Organisations working on vaccine: 
  
  Codagenix with Serum Institute of India

• Estimated date of first human trials:  By August 2020

5. Protein-based vaccine:

• Organisations working on vaccine:
  
  Novavax; Clover Biopharmaceuticals with GSK; Baylor College of Medicine, University of Texas Medical Branch, New York Blood Center and Fundan University, China; University of Saskatchewan, Canada; University of Queensland, Australia, and Dynavax; Vaxart; Generex; ExpreS2ion; Vaxil Bio; Sanofi Pasteur; iBio/CC-Pharming 

• Estimated date of first human trials:  By June 2020

Immune response: 

• It is not known how strong the immune response needs to be to protect against SARS-CoV-2; therefore, some of the vaccines being developed may not work;
• Before candidates reach clinical trials, investigators must also ensure they induce protective immunity, not immunopathology, as was seen in early attempts to develop a SARS-CoV vaccine after it emerged in 2002.