The world is tired of Covid-19 and other viral outbreaks. But it seems the virus is still not going away. Today, let’s reflect on the possible 4th COVID wave in Delhi/India, the circulation of SARS-CoV-2 variants across the globe, and the spread of monkeypox in the world especially the US and the availability of vaccines against it.
Fourth COVID Wave in Delhi/India?
As per a recent report (Zee News, Aug. 11, 2022), Delhi logged 2,146 cases and eight deaths in 24 hours. More than 50 per cent of these samples were associated with the new Omicron sub-variant named BA.2.75. The latest surge in cases in Delhi is possibly due to this strain, which has been shown to be much more transmissible than other variants.
It's not yet clearly known if BA.2.75 is more vaccine-resistant compared to other Omicron variants.
As the country continues to report over 15,000 cases daily, the Centre has advised the States to avoid large crowding events while celebrating Independence Day. The Delhi government has also made masking mandatory once again and has decided to impose a fine of Rs 500 on the violators.
Covid Variants Globally
BA.2.75 has been seen in a study of 90 samples in Delhi sent for genome sequencing (TOI, Aug. 10, 2022). This sub-variant has been found to infect people who have been previously infected, have circulating anti-COVID antibodies, or have taken COVID vaccines already.
This variant has also been dubbed Centaurus. The WHO has classified this strain only as a variant of interest (VoI). This possibly means that it’s not as virulent as Delta or the original Omicron variant, which are put in the category of variant of concern (VoC).
Overall, the number of cases due to BA.2.75 globally is relatively low; worldwide BA.4 and BA.5 are the dominant strains at present. Dr Eric Topol has dubbed BA.2.75 as a “scariant” as the strain has been found only in a few places in India (without competing BA.5 strain) and is not spreading much anywhere else. However, the concerning thing is that the Centaurus is more transmissible as well as relatively more vaccine resistant than other strains.
In the US, BA.5 accounts for over 87% of COVID cases.
Soumya Swaminathan, WHO Chief Scientist, warns that BA.2.75’s immune-evasive trait is a major threat. The strain has a clear growth advantage and may eventually spread to the rest of the world. Even if the Centaurus doesn’t spread globally, there is still the potential threat of new COVID sub-variants emerging and catching the world once again in its murderous clutches.
Ewen Callaway, writing in the leading science journal Nature (Aug. 10, 2022), says that the Centaurus (BA.2.75) is rising fast in India but hospitalization rates are low so far. As the rest of the world awaits the end of the surge caused by BA.5, a new sub-variant nicknamed Centaurus is rising fast in India. Though it has been detected in over 20 countries worldwide, researchers are divided on whether the rise in BA.2.75 cases should be treated as alarming or not. The strain was first detected in India in May 2022. The worrying trend is that surveillance of COVID variants is falling drastically in many countries.
According to Dr. Yunlong Cao, Peking University, prior infections by Delta variant protected Indians against BA.5, leaving an opening for BA.2.75 and the latter won’t prevail much outside India, especially in countries that weren’t infected seriously by Delta variant of SARS-CoV-2.
Monkeypox Cases Worldwide
More than 31,000 cases of monkeypox have been reported globally since Jan. 1, 2022; with over 10,000 of them in the US alone (CNN News, Aug. 12, 2022). Most people have recovered at home with no long-term problems. But doctors are puzzled about why some cases can be serious and, rarely, fatal. According to WHO, there have been two fatalities in Spain, one in Ecuador, one in Brazil, and one in India. There have been no deaths in the US so far.
People at higher risk from severe monkeypox include those with serious HIV, pregnant people, young children & infants, and people with eczema or atopic dermatitis. Babies are at higher risk as they don’t have fully functioning immune systems.
There are 3 strains of the monkeypox virus (a cousin of the smallpox virus): Congo. West African, and US strains. The US strain which is similar to the West African one causes milder disease. Monkeypox is endemic in Congo, where the Congo strain causes severe disease. It’s not known how and when monkeypox becomes severe in non-endemic countries.
The Monkeypox Vaccine
The only FDA-approved monkeypox vaccine offered in the US is called the Jynneos Vaccine, made by the firm Bavarian Nordic (The Washington Post, Aug. 11, 2022). The 2-dose regimen was approved for smallpox and monkeypox in 2019 for adults at risk for infection. More recently, the FDA has given an EUA for children deemed to be at high risk. The hitch is that currently the supplies are limited and the US authorities have ordered for additional doses up to nearly 7 million by mid-2023.
The US also has an older vaccine called ACAM2000, meant to protect against smallpox. It’s supposed to be effective against monkeypox as the two viruses come from the same family. But health authorities are hesitant to recommend ACAM2000 as it relies on live virus, posing a higher risk of severe side effects. Recipients of ACAM2000 could also infect others. Jynneos is preferred because it’s a non-replicating vaccine; so, it cannot make new viral particles and does not carry the same risk of side effects or infecting others.
Older people who got the smallpox vaccine in childhood may have some level of protection against monkeypox, according to WHO. But vaccination against smallpox is only 85% effective against monkeypox. As per CDC guidelines, people exposed to monkeypox who have not received a smallpox vaccine in the past 3 years must consider getting vaccinated with a monkeypox vaccine.
Treatments for Monkeypox
An antiviral drug developed to treat smallpox called TPOXX has been approved for monkeypox. But the medicine is in short supply. Vaccines for smallpox may provide limited protection against monkeypox. Those who have been immunized against smallpox may also be similarly protected. However, people below the age group of 40-50 are unlikely to have been vaccinated against smallpox as vaccination stopped in 1980 (HT, July 14, 2022). There is another vaccine called the Jynneos vaccine but it is not produced in large amounts yet.
COVID-19 seems far from over. As our immunity fades over time, there is the likelihood of the emergence of new sub-variants. Therefore, we all must strictly follow the Covid-appropriate behavior. We also must be watchful about the possibility of the monkeypox virus spreading across the country.
We also must ensure that the adult population in India is fully vaccinated at the earliest. The possibility of vaccinating children below the age of 12 must also be looked into. And, immunocompromised people and those above 60 years of age must be given the 2nd booster doses at the earliest, if feasible.