February 14, 2021
HIV and SARS-CoV-2: Variants happen
I have mentioned before that my first real passion in medicine was caring for AIDS patients and people living with HIV. I am an infectious disease doctor at heart, but I felt I was too old to do an extra 3 year fellowship since I started medical school when I was 32, which meant I was 39 when I finished my residency. Family Medicine ended up suiting me well and ultimately allowed me the chance to do what I wanted after all.
After graduating from medical school in 1990 and completing my residency in Family Medicine, I have been able to find work in clinics caring for people with HIV. I have watched the treatment of HIV change from no good treatments to treating with one pill a day, amazing advances over the years. I have had the privilege of working with some really smart colleagues who taught me so much about viruses, including viruses’ ability to mutate.
Mutations happen. We expect them. Different viruses have different modes of achieving the same goal; which is to use their host cells’ mechanisms to manufacture the building blocks needed to make new viruses. They turn a host cell into a virus factory. Because of the method some viruses use to make copies of themselves, mistakes happen in copying the DNA or RNA. Most mutations don’t change anything, but some make the virus less infectious or virulent, others can increase their reproductive advantage. The AIDS pandemic really showed how that worked. Up until HIV was studied, there were not a lot of antiviral medications, and none of them worked that great. When they first found meds like AZT that seemed to work with HIV, they quickly found that AZT and others would stop working because the virus would make mutations that could get around the med’s mode of action. Mutations occurred with other meds too. Called ‘resistance”, it means a medication no longer controls or treats the virus, if that virus has mutations resistant to that med.
Researchers in the mid 90’s decided to try 2 and 3 drugs together to see what would happen. That is when the big breakthrough came with AIDS. Taking 3 meds or a “cocktail”, with at least one of the meds attacking a different part of the replication process, was the ticket.The virus was suppressed and couldn’t replicate to make mutations. Suddenly lives were changed. People who were dying started to survive and then thrive. At first the cocktails were complex with multiple meds and multiple doses a day, with lots of side effects. Little by little, research study by research study, committed researchers, scientists, doctors, and patients, were able to make progress, so that today people with HIV can take one combination pill daily. Life expectancy is essentially normal if people can get the meds and stay on them. Resistance develops when people skip doses or stop and start meds due to costs, availability, access to care, and other reasons.
We learned that the HIV virus would make the same mutation over and over again if people did not take their meds regularly. Mutations like M184V and K104N became part of our regular vocabulary, just like the new UK B.1.1.17 and South Africa’s B.1351 variants are now.
Those variants are concerning and why we are still needing to follow masking guidelines and distancing restrictions, even if we have been vaccinated. These variants also are much more easily transmissible and are predicted to become the dominant strain in a few months. Even if we are protected from a severe case of COVID-19 and hospitalization or death, we may still be able to transmit the virus. I do not want to give the virus to anybody else, so I am still careful, even though I personally feel safer. Data is now confirming what we suspected- the UK variant is more deadly than the other strain. We also have evidence that the new strains may re-infect people who have had a different variant of SARS-CoV-2. New studies in the US show 7 variants with the same mutation, reinforcing the concept of convergent evolution. Scientists are tracking these variants and others to monitor for more dangerous developments. This New York Times graphic about the variants is a helpful guide.
Some data does reassure that the vaccines so far offer at least some protection from the new strains, especially prevention of hospitalizations and deaths due to COVID-19. Getting vaccinated is protective, but until we have improved vaccination rates, we will need to continue our vigilance.
These variants are not a surprise to people who have worked with viruses like HIV. We have learned about the evolutionary wiliness of viruses over the years. The research done on HIV and other viruses like Ebola have helped us make so much progress so quickly with SARS-CoV-2. Amazing really that there are several very viable, and very different, effective vaccines being given world wide in a year’s time. The work being done will be able to make effective vaccines for other viruses in the future, as well as easily adapting to target the new SARS-CoV-2 variants. In fact, some new vaccines against the new variants are already being tested.
Wash your hands, cover your nose, keep safe six, be grateful for science!
And finally, my caveat is that this is my experience and my opinions, which are subject to change as more information is available, and not related to the organization I work for. Thanks for reading.
https://www.seattletimes.com/business/dont-let-down-guard-on-virus-cdc-head-warns-amid-lethal-strain/
https://www.washingtonpost.com/world/2021/02/13/virus-variant-first-detected-uk-has-been-deadlier-study-confirms/
https://www.seattletimes.com/nation-world/mutated-virus-may-reinfect-people-already-stricken-once-with-covid-19-sparking-debate-and-concerns/
https://www.nytimes.com/interactive/2021/health/coronavirus-variant-tracker.html
https://www.nytimes.com/live/2021/02/14/world/covid-19-coronavirus/a-new-study-identifies-seven-us-virus-variants-with-the-same-worrying-mutation
https://www.seattletimes.com/nation-world/7-virus-variants-found-in-u-s-carrying-the-same-mutation/
https://www.sciencedirect.com/science/article/pii/S1879625718301081
https://www.nature.com/articles/s41591-021-01270-4
https://www.nationalgeographic.com/science/2021/01/how-covid-vaccines-may-lead-to-new-shots-for-other-deadly-viruses/