Thread by @miamalan

[Thread] 1. @sahpra says the #Sputnik #COVID jab could possibly make men more likely to get infected with #HIV. What does science say about this?
bit.ly/3lWjo24

2. 1 of #Sputnik’s 2 shots uses a common cold virus, adenovirus 5, as a vector. A vector is a safe germ that shuttles some of the genes of the #COVID19 virus into your body. For most shots, this is the gene of the spike protein on the surface of the virus. bit.ly/3vny7Gw

3. When your body recognises the spike protein, it makes antibodies + T-cells to fight it. That’s why jabs protect you @ falling seriously ill with #COVID19 — because they help your body to make soldiers in advance that can respond quickly to the virus in case you get infected.

4. So how on earth can a #COVID jab be linked to #HIV infection? It’s all about the Ad5 vector. A decade or so ago, scientists tested an #HIV jab on people. That jab, manufactured by Merck, also used the Ad5 virus as a vector. bit.ly/30KNhdJ

5. Merck’s jab was tested in two trials:
1. The STEP study (conducted in men and women at high risk of HIV infection the Americas, Caribbean + Australia)
2. The Phambili study (conducted in men and women in SA)

6. Halfway through the STEP study, scientists got concerned. When they analysed the first results it showed that more men (of a subgroup, see next tweet) in the vaccinated group contracted #HIV than in the unvaccinated group.

7. Most of the vaccinated men who got infected with #HIV had a few things in common:
* They were uncircumcised
* Had previously been infected with Ad5 (the way you get infected with germs when you get a cold) - so they had Ad5 antibodies
* Had had unprotected insertive anal sex

8. The STEP scientists stopped their study because of the higher risk of #HIV infection their jab posed to certain men. They also told the Phambili study about their findings. That study, which happened @ about the same time as STEP, was then also stopped. bit.ly/2YZYciH

9. When the Phambili researchers later analysed the results they did managed to gather before the study was halted, they also found an increased risk of #HIV infection among vaccinated, heterosexual men. bit.ly/2YZYciH

10. How common is Ad5 infection in SA (so how many men would have Ad5 antibodies that could potentially put them at higher risk of #HIV infection)? One study found about 80% of SAs have been infected with Ad5 (a common cold virus). bit.ly/3vr7vV0

11. What about Ad5 is it that could lead to a higher risk of #HIV infection? Scientists don’t yet know. They think it could be that Ad5 makes it easier for HIV to replicate, sets up more target cells for HIV to latch onto or that it dampens HIV immunity. bit.ly/3vxT15N

12. In Oct 2020, when #COVID19 was well underway + COVID jabs were in development, STEP/Phambili researchers got worried when they heard some jabs were using Ad5 as a vector. They wrote a letter to The Lancet to warn about the possible #HIV infection risk. bit.ly/3vxT15N

13. #COVID jabs that use Ad5 as a vector:
* #Sputnik (Russia; authorised in 70 countries)
* ImmunoBio (still in clinical trials, also being tested in SA)
* CanSino’s Convidecia, (developed in China, used in Hungary, Pakistan, Mexico, Chile, Argentina, Malaysia, Ecuador)

14. #Sputnik applied for emergency use approval (Section 21 approval) of its #COVID19 jab with @sahpra1 on 23 Feb 2021. Because of the concerns re Ad5 + #HIV, Sahpra asked them for data to prove the jab doesn’t lead to an increased risk of HIV infection. bit.ly/3jhR74f

15. But #Sputnik hasn’t sent @sahpra1 any such data, which means that Sahpra can’t certify the jab as safe to use. It could very well be safe, but without data to prove that it is, Sahpra can’t be sure.

16. Why do other countries use #Sputnik if there’s a risk of #HIV infection? In countries where #HIV infection rates are low, the possible increased risk of infection is not a big issue, as there aren’t many HIV+ people to infect others. But SA has millions of people with #HIV.

17. How many people with #HIV does SA have? Over 8.23 million, according to Stats SA’s 2021 mid-year population estimates. 1 in 5 adults between 15-49 years of age are HIV-positive. statssa.gov.za/publications/P…

18. Sahpra has its own standards when reviewing safety + efficacy data. Other regulatory bodies could make different decisions. But it's NB to note that @SAHPRA1 is held in high regard by large regulatory bodies such as the FDA and EMA because it has rigorous review processes.

19. #Sputnik has also applied for emergency use listing with the WHO. Jabs on the emergency use list are acknowledged as safe + effective. #COVAX can buy them to distribute to countries. But the WHO too says they haven’t received enough info to approve Sputnik for the list.

20. So what now? @sahpra1 has kept open its rolling review of #Sputnik (rolling means data can be submitted as it becomes available). If Sputnik submits sufficient safety data, then Sahpra will review it and make a decision on whether it will approve the jab for use or not.

21. What type of safety data does Sahpra need?
* For now, animal model data will be sufficient
* But #Sputnik would then need to also continuously collect real life data on potential #HIV infections from countries with high HIV burdens where the jab has been rolled out

22. Want to see this all in one place? Read @A_AbdoolKarim and @vandykjoan easy explanation of the science behind @Sahpra's decision to not approve the #Sputnik V jab at this time: bhekisisa.org/health-news-so…