Initial findings of research, conducted by the Thai Department of Medical Sciences, show that the COVID-19 Omicron BA.4 and BA.5 sub-variants are more serious than the BA.2 sub-variant, says the department’s director-general, Dr. Supakit Sirilak.

He said today (Monday) that the findings are based on random checks of 570 COVID-19 cases, conducted between July 2ndand 8th, by the Department of Medical Sciences. Among them,280 were found to be infected with BA.4 and BA.5 sub-variants, 283 with the BA.2 sub-variant, 5 cases of BA.1 sub-variant and 2 cases which could not be clearly identified.

Dr. Supakit said that 71.95% of BA.4/BA.5 infections and 28.05% of BA.2 infections were not severe.

Of 13 severe cases, including those involving lung infections,ventilators or death, 76.92% were BA.4/ BA.5 infections,while 23.08% were BA.2.

From these initial findings, he said that BA.4 and BA.5 sub-variants are more likely to cause more serious symptoms than the BA.2 sub-variant, adding that the incidents of BA.4 and BA.5 sub-variant infections are tending to increase in Thailand, with more serious cases in Bangkok than for BA.1 and BA.2 sub-variants.

He admitted, however, that the number of cases examined by the Department of Medical Sciences is not enough to determine with certainty that BA.4 and BA.5 are more serious.

He urged hospitals to send more specimens from severe cases, including lung infections, ventilator cases and fatalities, to the department for further study.

Meanwhile, Dr. Chakkarat Pittayawonganon, head of the Division of Epidemiology at the Disease Control Department, said that disease control measures may need to be adjusted again, if there are more BA.4 and BA.5 cases which require hospitalisation and ventilators or there is an increase the death rate to 40 a day.

The new guidelines, set by the Disease Control Department,stipulate that, if hospitalisations increase to more than 4,000 a day, the department will recommend that people wear face masks all the time while they are outdoors, in crowded venuesand in those with poor ventilation with strict social distancing. Hospitalisations today were 1,811.

If patients requiring ventilators increase to 400-500 a day, the medication and treatment process will be adjusted, said Dr.Chakkarat, adding that, if the fatality rate increases to 40 a day, disease control measures will also be adjusted.

He disclosed that, in the past two weeks, lung infections haveincreased from 638 cases on June 28th to 786 cases today,while the number of patients requiring ventilators has climbed to 349, from 290.

He predicted that, during the long public holidays in July, infections in the provinces may increase and peak during the 33rd week of the year and lung infection cases will put pressure on hospital bed availability.