Only hospitalisation rate can't determine wave's peak: Experts

New Delhi: One cannot conclude that the peak of the ongoing wave of the coronavirus pandemic is over in Delhi solely on the basis of hospital admission data, experts said Thursday as the number of cases and positivity rate continue the upward trend in the city.

Hospitalisation has remained relatively low in Delhi, and Health Minister Satyendar Jain said Wednesday that the plateauing of hospital admissions indicates that the ongoing wave has peaked and cases may go down soon.

However, according to noted epidemiologist Dr Chandrakant Lahariya it cannot be concluded that the peak is over solely on the basis of hospital admission data.

The reason being that people get admitted to hospital only some days after they have developed the disease, he said. "So, there is a lag of 6-7 days."

"The number of daily cases and the positivity rate should be used to determine the peak. Hospitalisation depends on the criteria adopted for admission (in a particular region). Of course, hospitalisation is an important parameter for public health planning purposes, but not for describing a peak," he said.

Director of the National Institute for Implementation Research on Non-Communicable Diseases, Jodhpur, Dr Arun Sharma said, "Epidemiologically, the peak of a wave is determined with the help of the rate of transmission, the number of infected people and the uninfected susceptible population. It can be plotted on a

graph but the ground reality is always different from epidemiological modelling."

The positivity rate is the most important factor because the number of cases may increase or decrease depending on the number of tests conducted, he said.

"Only when the test positivity rate start declining, we would know we have passed the peak," Dr Sharma said.

"In case of Omicron, most cases are mild and do not require hospitalisation. So, the wave has peaked or not cannot be determined looking at hospital admissions," he added.

Jain had said on Wednesday the plateauing of hospital admissions over the four days before that indicates the ongoing wave has peaked and cases may go down soon.

Dr Rajeev Jayadevan, vice chairman of the research cell of Kerala's unit of Indian Medical Association, said the number of hospital admissions is the best indicator of the severity of the ongoing wave of the pandemic, but it is difficult to say whether the wave has peaked or not.

"In 2020, testing was being done with an intention to find a case and isolate them. Now, it is not possible. Everybody is turning out to be positive. How many are we going to chase down the road?" he said.

He said such an exercise takes away manpower from more urgent needs.