Meningococci evades pandemic lockdown measures

A group of teenagers sit and smile.

A recent University of Adelaide study has found a significant increase in the rate of meningococcal bacteria in the throats of first-year university students in 2020 despite COVID-19 containment strategies. Photo: iStock.

Social distancing, online classes and the temporary closure of pubs, bars and nightclubs failed to stop the spread of meningococcal bacteria among school leavers, a new study from the University of Adelaide has found.

“The proportion of adolescents with potentially harmful meningococcal bacteria in their throats increased 87 per cent – from 3.7 per cent in February and March 2020, to 6.8 per cent in August and September 2020, when COVID-19 restrictions were in place,” said Professor Helen Marshall AM, Deputy Director of the University of Adelaide’s Robinson Research Institute and the 2022 South Australian of the Year.

“The spread of meningococcal bacteria among university students generally goes up as the year progresses, but we thought it would have decreased following the introduction of COVID-19 containment strategies that kept people apart and reduced physical interactions.

“We were quite surprised with the results.

“Vaccinating those people who are at the most significant risk of meningococcal disease remains critical.”

The researchers swabbed 1338 school leavers, who consented to be involved in the study, between the ages of 17 and 25, with an average age of 18.6, during Orientation Week in 2020, before following up in August and September, 2020.

Meningococci live in people’s throats and spread through respiratory droplets or saliva from human to human.

“The spread of meningococcal bacteria among university students generally goes up as the year progresses, but we thought it would have decreased following the introduction of COVID-19 containment strategies that kept people apart and reduced physical interactions. Vaccinating those people who are at the most significant risk of meningococcal disease remains critical.”Professor Helen Marshall AM, Deputy Director of the University of Adelaide’s Robinson Research Institute, and the 2022 South Australian of the Year.


“Activities like smoking, intimate kissing and close contact in pubs, clubs and parties typically lead to increased transmission,” Professor Marshall said.

“Most people who carry the bacteria in their throats are asymptomatic, but a small number of people develop invasive meningococcal disease when the bacteria enter the bloodstream.

“Meningococcal disease kills approximately eight per cent of infected people and causes permanent disabilities in up to 40 per cent of cases.”

Study investigator Dr Mark McMillan said a dramatic reduction in meningococcal disease in South Australia – from 27 cases in 2019 to just five in 2020 – was partly due to the introduction of infant and adolescent Meningococcal B and Meningococcal ACWY vaccination programs from 2017.

“However, a reduction in meningococcal cases globally has been observed in places without similar vaccination programs,” Dr McMillan said.

“The observed reduction in Australia and other countries is likely due to reduced levels of influenza in 2020.

“Influenza and other viruses are thought to damage the throat lining and increase the chance of meningococcal bacteria entering the bloodstream.

“It does not appear to be due to a reduction in the spread of the bacteria in South Australia.”

The BPartofIt School Leavers Study results have been published in the Pediatric Infectious Disease Journal.

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