The National Institute for Communicable Diseases (NICD) published its latest Covid-19 modelling report, looking at how the spread of the virus could accelerate in the coming months, bringing about a third wave of infections locally.
According to the NICD, the purpose of the report is to assist government planners and decision makers – as well as the general public – to track the start of the third wave, as well as provide planning support.
The NICD said that that the data does not predict when the third wave will hit, but rather what shape it will take and what will drive it. In this regard, it said that seasonal factors will play a part, echoing views from medical experts who believe the third wave will likely hit around the end of May entering June, coinciding with the shift to winter.
This will be exacerbated by behaviour changes among the population – complacent after the last wave – as well as ongoing viral mutation and waning immunity from the last two waves of infection, it said.
The modelling data shows that, should new variants of the Covid-19 virus be kept at bay, the third wave of Covid-19 will likely peak lower than the second wave – while hospital admissions are also expected to be lower.
However, should a highly-transmissible new variant enter the picture, the peak could be the same as the second wave, if not worse. As always, keeping infections and hospital admissions low requires individuals to adhere to restrictions.
Shape of the third wave
The shape of South Africa’s third wave depends on various factors, but broadly hinges on government’s and individuals’ response, the NICD said. A quick, strong response in the modelling shows a lower peak, with fewer deaths. A slow, weak response has the opposite effect.
Across scenarios, in the absence of a new variant, the NICD expects the peak of the third wave to be lower than the second wave.
Younger age groups are expected to have fewer admissions than in the second wave, while provincial projections show substantial variation of the size of the third wave between provinces, reflective of different age distributions and prevalence of comorbidities.
The third wave is anticipated to hit Gauteng hardest across all scenarios, due to the higher concentration of working-age adults and people with co-morbidities in the province, and the lower estimates of seroprevalence – the level of a pathogen in a population, as measured in blood serum.
“Across provinces, the time from initial increase in transmission to the peak is on average 2-3 months. It should be noted however, that these results are subject to substantial uncertainty due to the incompleteness of the seroprevalence and other underlying data, and unknown future population behaviour,” the NICD said.
Variants and vaccination
Notably, the report has two caveats – the data does not factor in government’s vaccination rollout, and it assumes that only the local 501Y.V2 of the variant is at play.
South Africa’s delayed vaccination rollout restarted at the end of April, with only 290,000 healthcare workers inoculated under the Sisonke programme at the time. To date, 318,000 people have been vaccinated, with government setting the target to reach 500,000 by mid-May.
Phase 2 of the rollout is expected to start on 17 May, where essential workers and vulnerable individuals – including the elderly and those with comorbidities – will be allowed to register for the jab.
To reach government’s stated goals of 16.5 million people covered by October, it needs to vaccinate over 100,000 people daily. Under the Sisonke programme, it managed around 6,000. This is in part due to low vaccine availability – something which should be remedied with access to various vaccines in the coming months.
However, medical experts have said that the current number of vaccinations are too low to have an impact on herd immunity related to Covid-19.
The NICD’s second caveat – no other variants of the virus being taken into account – is notable given developments in India, where new variants are emerging amid a massive outbreak in the region.
India’s tally of coronavirus infections on Monday rose to just short of 20 million, propelled by a 12th straight day of more than 300,000 new cases, Reuters reported, noting that scientists predict the pandemic could peak in the coming days.
A highly infectious variant of the virus has emerged from the region, and has already jumped to countries like Indonesia, prompting other territories to shut down travel to and from the South Asian country.
The variant, B.1.617, has reportedly reached at least 17 countries, from Britain and Iran to Switzerland, sparking global concern and spurring several to close their borders to people travelling from India.
The Indian outbreak has sparked concerns locally, prompting the Ministerial Advisory Committee (MAC) to make recommendations to government on potential restrictions for South Africa.
“The challenges we have seen in India are very serious,” health minister Zweli Mkhize said in address last week (30 April). “We have received an advisory from the ministerial advisory council that we have to consider some restrictions and we are now going through that,” he said.
The NICD said that the variant has not been detected in South Africa.
“Testing of Covid-19 positive samples from travellers entering South Africa from India and their close contacts will be prioritised,” it said. “This will enable us to detect the B.1.617 and any other variants in a timely manner.”
Global Covid-19 infections have hit 153.5 million confirmed, with the death toll reaching 3.22 million.
In South Africa, over 4,500 new cases were reported over the weekend, taking the total reported to 1 584 064. Deaths have reached 54,417, while recoveries have climbed to 1,507,778, leaving the country with a balance of 21,869 active cases.