Thailand says 40-year-old vaccine safe to use against monkeypox
Half a million doses of smallpox vaccine that have been in cold storage for the past 40 years are safe to use to prevent monkeypox, health authorities said on Friday.
The news comes after Thailand recorded its first confirmed case of monkeypox – a 27-year-old Nigerian man who was hospitalised after arriving in Phuket last week. The infected man reportedly left the hospital without authorisation on Thursday and is now being sought by police, immigration and disease control officials.
A sample of the stored smallpox vaccine was sent for testing by the Public Health Ministry’s Department of Medical Sciences in May.
Department director-general Dr Suphakit Sirilak said on Friday that the vaccine passed five quality tests – for appearance, physicochemical properties, safety, identity, and potency.
The smallpox vaccine was manufactured in 1979 and 1980 and stored in 10,000 tubes, each of which contains 50 doses. The doses were then stored in powdered form and refrigerated at between 2 and 8 degrees Celsius.
Suphakit said they could be used in a public health emergency if the disease spreads in Thailand and the government is unable to purchase fresh vaccine stocks.
The World Health Organisation has approved three types of smallpox vaccine – second-generation, third-generation and fourth-generation. Meanwhile, the US Food and Drug Administration has approved third-generation vaccines for use to prevent monkeypox.
