A study published in Oxford University Press’ Journal of Public Health has found that 36% of Karachi’s residents have coronavirus antibodies and if current trends continue, there is lower chance of a second wave hitting the city due to the masses having achieved herd immunity.
Herd immunity is a form of indirect protection from a contagious disease that occurs when a sufficient percentage of a population has become immune to an infection, whether through vaccination or previous infections, thereby reducing the likelihood of infection for individuals who lack immunity.
Herd immunity develops when a significant chunk of the population has developed antibodies of a disease following infection, thereby reducing the chance of passing it on to others, which the researchers say is 60-70% of the population.
According to the study, conducted between May and July, if 36% of the adult population of Karachi is supposed to be seropositive (positive for COVID-19), then it can be assumed that in the next two-to-three months “∼60% of general population will become seropositive”.
“This assumption or theory if proven right then it will reduce the chance of a second wave in Karachi and increase the possibility of acquiring herd immunity,” the paper adds.
Anadolu Agency quoted lead researcher, Dr Samreen Zaidi, as saying that further studies show that the seroprevalence rate has reached 60%, as was expected.
“We, on the basis of a gradual drop in cases, and other relevant factors, assume that there are low chances of a second wave of coronavirus,” Zaidi told Anadolu Agency.
However, she acknowledged: “Assumptions are assumptions.”
“The only limitation of this study is that our sample size is small. Therefore, we have recommended further and wide-ranging research on the government level to double-check the results of this study,” she said.
Hematologist and head of NIBD, Dr Tahir Shamsi, also claimed that the country has “almost” attained herd immunity, indicating that there are low chances of a second wave of the pandemic.
“The data this study shows is until July. We are in September now, and the latest statistics, and testing results suggest that the seroprevalence or immunity rate is almost 60% now,” Shamsi told Anadolu Agency.
He said the latest findings would be published after a month.
