Sewage testing to begin
Scientists have gathered sewage from around New Zealand to test it for Covid-19.
The Institute of Environmental Science and Research (ESR) has confirmed that testing of the samples – already gathered from around the country, including from cluster areas – will begin this week.
ESR expects the initial results, being done at its Kenepuru Science Centre in Porirua, to be back later this week.
Scientists spent the past week developing their methods for testing the samples and making sure a laboratory was set up to test the wastewater.
Given the low presence of known Covid-19, ESR said it was unsure if it would detect any of the virus. ‘‘However, we’re seeing anecdotal evidence from overseas that it is possible to detect low limits of the virus.’’
The process is essentially sampling the nation’s sewage for traces of the genes unique to the coronavirus.
‘‘Wastewater testing will allow for further certainty in the later stages of the Covid-19 pandemic, as it will indicate whether the virus has been eliminated or is present and remaining undetected by other testing methods,’’ according to a coronavirus national situation report sent out yesterday.
‘‘This testing regime will also be able to reach a large sector of the population at once, decreasing reliance on testing symptomatic people to determine a continued presence of the virus in New Zealand.’’
Director-general of health Dr Ashley Bloomfield was asked about the idea yesterday.
‘‘It is one of the options that you can use as overall surveillance,’’ he said.
‘‘For example, you will know that there is testing of sewage done for illicit drugs to get an idea of where and what the prevalence of use might be in specific communities.’’
The testing was highly sensitive ‘‘but you would still need a reasonable rate of infections in the community to be able to detect it’’, he said.