Last week saw the rapid fall in daily Covid-19 infection rates since these peaked in the middle of December suddenly cease and convert into a plateau, not getting much worse, but no longer dropping, while death rates may have peaked towards the end of the week, although after the worst week so far in the present wave.
Daily numbers of new cases tend to fluctuate, falling over weekends and public holidays and rising shortly afterwards possibly as a result of late testing and late reporting followed by a burst of activity.
Hence the seven-day rolling average is frequently used to identify trends by ironing out the daily kinks.
When this is plotted on a graph it is easy to see the progress of the fourth wave, with infection rates suddenly soaring from the last week of November to reach record highs in the middle of December, and then equally rapidly starting to fall.
But last week that fall stopped. Instead we saw the trend hover around 1 500 new cases a day for several days, rising some days and falling the next.
One Saturday the number of recorded cases did drop below 1 000 to reach 955 but that could well be attributed to Saturday being a public holiday and many people deferring their tests, or the test results being recorded late in the statistics.
We saw the same on Boxing Day. In any case the trend line of the rolling average maintained a consistent horizontal line.
Deaths were climbing during the week. This was expected as death rates tend to lag about two weeks behind infection rates.
This is because severe symptoms that can lead to death take anything between one and three weeks to develop for most patients. So at the beginning of the wave we saw very few deaths and only minor daily rises in rolling average.
But the death rates kept climbing as infection rates starting falling, and last week saw the two highest daily death tolls recorded in the present wave, 32 and 30, although some of those deaths were late reports. Looking at the rolling average this reach its record high for the wave on Thursday with 20,3 a day for the previous seven days.
That started edging down on Friday and Saturday, reaching 18,9 at the end of the week. But it is probably too early to say whether this is the start of a downward trend. We have had the odd small decline in the average a couple of times before and then the trend line went back to its upward climb.
During last week between Sunday and Saturday there were 10 467 confirmed new cases and 132 deaths, although the seven-day death total did hit 142 on Thursday. One serious piece of good news was the falling number of active cases from 38 887 a week earlier on Christmas Day to 26 786 on New Year’s Day. This was only just over half the highest number recorded, 51 186 on December 18.
The fall was due to most of those who became infected in the first fortnight of the wave getting better and being cleared by the medical authorities.
Vaccinations were low during the week, just 67 190 doses being given. This was the lowest weekly total since the third week of June and demonstrates the difficulty of persuading all Zimbabweans aged 16 and over to line up for their free shots.
Vaccine supplies are more than adequate and medical teams can cope with a far higher work load.
About one in 12 of those recorded jabs were third doses, with 5 673 third jabs given during the week. Almost all of the booster shots at this stage are going to frontline medical staff, who take vaccination extremely seriously since they see daily the huge advantages.
One milestone passed during the week was seen on Thursday when Zimbabwe finally reached the point where more than a third of those aged 16 and over were now fully vaccinated with both jabs.
By Saturday the number with both jabs was 3 140 345, about 33,45 percent of the 16+ age group and 20,94 of the estimated 15 million total population.
The number who had entered the programme by accepting the first jab was 4 129 952, about 43,99 percent of the 16+ population and 27,53 of the total population. However, a fair number of those who lined up for their first dose did not go back after two weeks for the second. There are still 989 607 people with just one shot, with just under 323 000 second doses in December, along with just under 328 000 first jabs and a little over 5 100 third jabs.
So far Zimbabwe has used 7 275 920 doses since the start of the vaccination programme. Even with unavoidable modest wastage that still means there are good stocks of vaccine in the country and good supply chains.
In place the second more stocks are required. What is missing is larger numbers lining up for their entitlement of free doses.