COVID-19:
In China, the relaxation of COVID-19 restrictions has continued, including opening up of travel with lifting (from 8 January) of quarantine requirements for arrivals – although there will still be a requirement for pre-travel COVID testing. Under the “category B” management of COVID-19, case data will only be published once a month, according to the China CDC on Tuesday. Anecdotal reports of very high numbers of cases, hospitalisations, and deaths are quite consistent with recent forecasts.
Phylogenetic analysis of the latest SARS-CoV-2 sequences from several Chinese regions reveals that the variants currently circulating in the country are the same as those seen circulating globally in the second half of 2022, particularly the Omicron sub-lineages BF.7 and BA.5.2. There is no evidence of a new variant. Nevertheless, several countries (including India, Japan, Italy, Malaysia, and now the USA) as well as Taiwan are implementing COVID-19 testing for travellers arriving from China.
Commentary posted on the US decision, by renowned epidemiological modeller Adam Kucharski, was:
“uncontrolled domestic transmission will grow exponentially while importations grow linearly. In other words, we’re much more likely to get an infection from a fellow resident than a traveler.” Similar thinking is outlined in a statement reported (on bbc.com) from the European CDC which noted:
- High levels of Covid in China are anticipated given the country's low immunity and recent relaxation of its rules
- But higher immunity in the EU means a Covid surge in China is not expected to impact the bloc
- The Covid-19 variants circulating in China are already circulating in the EU
- Potential imported infections from China are "rather low" compared to the number of infections already occurring in the EU
- And citizens in the bloc have relatively high vaccination and immunisation
There was a WHO press briefing on 21 December which discussed the China situation and is interesting, the transcript is available here (note in particular the section from 20 minutes to 42 minutes): https://www.who.int/multi-media/details/who-press-conference-on-global-health-issues---21-december-2022
Elsewhere: The US reports a gradual increase in its rate of COVID-19 cases, likely indicating a new epidemic wave. Several other countries/regions have reported recent increases in new COVID-19 cases, including Hong Kong, South Korea, France, Australia, New Zealand, and Brazil along with Japan which has seen higher daily death rates than at any time previously.
Some relevant/interesting papers:
From Hong Kong, a study on vaccine protection by Tsang et al: https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(22)00732-0/fulltext
Two doses of either vaccine did not provide significant protection against COVID-19 infection. However, receipt of a BNT162b2 booster or CoronaVac booster was associated with a significantly lower risk of omicron BA.2 infection and symptomatic infection. The findings confirm the effectiveness of booster doses to protect against mild and asymptomatic infection.
A Study in Bristol by Hyams et al: https://www.thelancet.com/journals/lanepe/article/PIIS2666-7762(22)00252-6/fulltext
Independent of other variables, including vaccination, Omicron variant infection in hospitalised adults was associated with lower severity than Delta. Risk reductions were 58% for supplementary oxygen with >28% FiO2 and 67% for WHO outcome score >5. Younger age and vaccination with two or three doses were also independently associated with lower severity.
A small US NIAID/NIH study reported in NEJM showed (not unexpectedly) serological benefit from bivalent boosters against subvariants BA.2.75.2, BQ.1.1 and XBB – Davis-Gardner et al: https://www.nejm.org/doi/full/10.1056/NEJMc2214293
Lancet reported a UK multicentre randomised trial which showed molnupiravir didn’t significantly reduce hospitalisations or deaths amongst high-risk vaccinated adults in the community – Butler et al: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(22)02597-1/fulltext
Other infections:
Scarlet Fever numbers in UK were reported to have been much greater than thought with 24 deaths in children recorded, and an increase in Strep A infections also being reported in France, and also in areas of the USA.
In Australia, there have now been 10 cases of Japanese Encephalitis, with one recently in South Australia. This mosquito-borne infection appears to be becoming established in Australia with some 44 cases since early 2021.
Cholera and measles continue to cause large outbreaks in a number of low and middle income countries.
Over 6000 malaria cases were reported in Panama already this season.
Best wishes to all for the New Year period; I will update again as appropriate.
David Powell
IATA Medical Advisor