Booster shots against Omicron wanes within 10 weeks

Five days of isolation are enough to mix with other people for those who test positive test to Covid-19 but are without symptoms. [Courtesy]

Experts are advising that isolation period for patients with of Covid-19 be shortened from 14 to five days.

The Centers for Disease Control and Prevention (CDC) which recommended shortening quarantine period after the highly transmissible Omicron variant was reported to be “sending daily caseloads soaring in Kenya and other countries.”

CDC says in its latest report cites growing evidence that “the virus is most contagious in the two days before and three days after symptoms develop,” but those “with symptoms after five days are encouraged to remain at home.”

Besides isolating for five days, the report further those exposed to coronavirus and have are ye to get booster shots to “wear masks around others for an additional five days” but those exposed to the infection and have received booster shots do not need to quarantine, but should wear a mask for 10 days.

Dr Evans Amukoye, the KEMRI Director of Centre Respiratory Diseases and Research concurs that five days of isolation are enough to mix with other people for those who test positive test to Covid-19 but are without symptoms.

However, Dr Amukoye warns that “booster protection against symptomatic Covid caused by the Omicron variant wanes within 10 weeks.

But vaccines specialist Dr Moses Mwangi believes booster shots will continue to provide significant protection against hospitalization and deaths.

And though Kenya has embraced booster doses, the third injection for people who have been fully vaccinated against the coronavirus,  Dr Mwangi reveals that both the initial two-shot series and booster doses – of AstraZeneca, Pfizer and Moderna  “were less effective and waned faster against Omicron than against Delta.”

The chairman of Kenya Society for Clinicians Dr Joseph Aluoch says among people “who received an AstraZeneca primary course, vaccine effectiveness was around 60 percent two to four weeks after either a Pfizer or Moderna booster, then dropped to 35 percent with a Pfizer booster and 45 percent with a Moderna booster by 10 weeks after the booster.”

Dr Aluoch observes that those who had received all recommended vaccine doses, including boosters, do not need to quarantine at home following high-risk exposures. But getting a third dose of either Pfizer, Moderna or Astra-Zeneca  Covid-19 vaccine offers “significant increase in  protection against Omicron variant in elderly persons.

Meanwhile, the US Food and Drug Administration (FDA) has authorized a second antiviral pill for Covid but experts say it should not be preferred over other treatments.

The US agency cleared Merck’s Molnupiravir “for adults who are vulnerable to becoming severely ill from Covid-19 and for whom alternative treatment options are ‘not accessible or clinically appropriate.”

The FDA’s “decision reflects concerns that Merck’s pill is only modestly effective and carries possible safety risks. The drug is said to cut the risk of hospitalization and death in high-risk patients by 30 percent when given within five days of symptom.  The drug can be used by people as young as 14 years.