COVID Booster: Caregivers lost to COVID-19, vaccine hesitancy in drug users, and social distancing reduces vaccine resistant strains

Cosmos Magazine


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More than five million kids have lost a parent or caregiver to COVID-19

New international modelling has estimated that a staggering 5.2 million children around the world have lost a parent or caregiver to COVID-19 since the start of the pandemic. The number of children affected had doubled between May and October 2021.

The study used demographic, mortality and fertility data from 20 countries to estimate the loss of parents and caregiver grandparents due to the pandemic. Losses were highest for adolescents aged 10-17, and children were three times more likely to lose a father than a mother.

The authors cautioned that, due to time lag and limited data availability for some countries, the true number of children orphaned due to COVID is likely even higher.

“Real-time updated data suggests the true totals reached 6.7 million children as of January 2022,” said lead author Juliette Unwin of Imperial College London in the UK.  

“While our current study looked at estimates through October 2021, the pandemic is still raging worldwide, which means COVID-19-related orphanhood will also continue to surge.”

Caregiver loss exposes children to increased risk of poverty, exploitation, abuse, and poor mental health.

Injecting drug users in Australia have high levels of vaccine hesitancy

Australian research has revealed high levels of vaccine hesitancy among injecting drug users.

The study interviewed over 800 people in Australia who inject drugs and found that 48% were hesitant to receive a COVID-19 vaccine – a percentage substantially higher than the general population.

The most common reported reasons for hesitancy were vaccine safety and side effects. However, only 9% reported that they would definitely not accept any vaccines.  

The interviews were conducted in June-July 2021, early in Australia’s vaccine rollout and third wave of COVID-19 infections.

People who used injected drugs are likely more susceptible to poor health outcomes from COVID-19 infection and can experience difficulties in health care access due to stigma and economic disadvantage. Despite these risks, injecting drug users were not a priority target population for Australia’s COVID-19 vaccine rollout.

Social distancing likely reduces risk of vaccine-resistant SARS-CoV-2 strains

An international study published in Nature Human Behaviour suggests that maintaining social distancing policies as COVID-19 vaccines are rolled out lessens the risk of vaccine-resistant strains emerging.

The study used vaccination and infection data from six countries (Israel, US, UK, Brazil, France and Germany) to model infection dynamics and viral evolution in different scenarios of social distancing and vaccination rates.

The results suggested that the emergence of vaccine-resistant strains is more likely when vaccine uptake is slow, or when vaccine uptake is fast but social distancing measures are not observed.

However, if vaccine uptake is fast and social distancing is maintained – which decreases the rate of new infections – the chances of a new vaccine-resistant strain are considerably lower.

For example, the researchers estimated a 2% chance of a vaccine-resistant mutant virus emerging in a country of 100 million people if 10,000 new infections per day are tolerated and one million people are vaccinated per day. This probability jumps to 10% if the same vaccination rate is maintained but 50,000 new infections per day are allowed.

Severe complications of COVID-19 extremely rare in vaccinated teens

A US study has found that the risk of multi-system inflammatory syndrome (MIS-C) is extremely rare – literally one in a million – in teenagers who have received at least one dose of a COVID-19 vaccine.

MIS-C is a rare but severe condition associated with SARS-CoV-2 infection in children and adolescents. It is thought to be caused by an overreaction of the immune system in response to infection. Symptoms include fever, rash, eye redness, gastrointestinal symptoms, and organ failure.

The study identified only 21 MIS-C cases in young people aged 12–20 who had received at least one vaccine dose, in a period during which over 21 million people in this age group received at least one vaccination.

By contrast, earlier estimates of MIS-C risk among unvaccinated young people put the number at 200 cases per million.

“Our results suggest that MIS-C cases following COVID-19 vaccination are rare and that the likelihood of developing MIS-C is much greater in children who are unvaccinated and get COVID-19,” said author Anna R. Yousaf, of the US Centers for Disease Control and Prevention (CDC).

Children appear to produce fewer aerosol particles than adults

Transmission via aerosol – tiny droplets produced when breathing out – is a major route for SARS-CoV-2 infection. A team of German researchers have reported that children produce lower volumes of aerosols when speaking and singing compared to adults.

The researchers used a laser particle counter to measure aerosol particle emission rates while at rest, speaking, singing, and shouting, in 15 children aged 8-10 and 15 adults. All were members of semi-professional choirs.

Overall, the children produced aerosol volumes around four times lower than adults, through values varied among individuals in both groups.

The researchers suggested their results, together with other factors, could inform more precise COVID-19 risk management scenarios for children in schools and extracurricular activities. However, they cautioned that the study does not amount to a recommendation to be less stringent in managing COVID-19 risk for children.

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