With cases of Covid-19 in Malta on a continued increase for the past three weeks some five months after the first case was found, many have been looking back towards the first wave of the virus in an attempt to draw comparisons.

The Malta Independent analysed both waves, comparing the two with all the publicly available data at hand, in an effort to see where they converge and where they diverge.

When taking into consideration the first wave of cases, one can look at the period between 16 March and 21 April – a period of 37 days after which point cases began to level off.

16 March – nine days after the first Covid-19 case was found – saw nine new cases, while 21 April saw 12 new cases before a decrease in the number of cases being found occurred.

Considering the current wave – and we can call it a wave because there is ongoing transmission rather than transmission which ceased after a couple of days – we can look at the 18-day period between 23 July and the day of writing, Sunday 9 August.

23 July is the day that the first case related to the Hotel Takeover – the first cluster of this new wave – was found.

422 new cases between March and April, 269 local cases since 23 July

In terms of sheer numbers, a total of 422 cases were found in the 37-day period which we have taken as constituting the first wave of the virus.

The highest number of cases found in a single day was 52 on 7 April, followed by 38 being found two days later.

Meanwhile, looking just at the numbers, a total of 370 cases have been found in the last 18 days.

However, a hefty chunk of those cases are migrants who were rescued in the Mediterranean and brought into Malta.  All migrants brought into Malta are immediately isolated and quarantined and, since March, are tested for Covid-19. 

Three groups of migrants were rescued in the past 18 days, out of which 101 tested positive for Covid-19.  Due to the fact that these migrants are isolated immediately upon arrival, their testing positive – while it does increase the number of active cases in Malta – does not have any bearing or effect on the local, community transmission of the virus itself.

So, for the benefit of this comparative analysis and to have the clearest possible picture of what the local transmission of the virus is constituted of, we will exclude the 101 migrants from the equation.

Once doing that, the number of cases found in the community in the past 18 days amounts to 269.

The highest number of cases found in a single day was 54 on 9 August - yesterday, followed by 49 two days prior.

132 out of 269 local cases related to clusters

The bulk of the cases in the current wave are largely down to clusters – although sporadic cases, which are cases where the source of the transmission of the virus unclear or not known, are now on the increase as well.

The wave gained momentum largely through two clusters, which were later joined by a third and then a fourth in recent days.

The first cluster was that related to a weekend-long party called Hotel Takeover, which took place at the Radisson Blu resort in St. Julian’s.

The first case here was detected on 23 July, and the cluster then expanded to include a total of 20 cases.

Some days later, a case detected said that he had attended activities related to the Santa Venera feast.  A public health alert was issued, and this cluster of positive cases now amounts to a total of 33 people.

The third– and by far the most infectious – cluster detected is referred to simply as the Paceville cluster. The exact source of where this cluster began is not known publicly, with Public Health Superintendent Charmaine Gauci simple saying that it was related to a number of establishments in the entertainment zone, but we do know that the cluster now includes 49 people.

A fourth cluster meanwhile is developing at language schools, with a total of 23 people being linked by health authorities to such establishments.

Another seven cases announced on Saturday have been linked to a Confirmation party as well.

This effectively means that 132 of the currently 269 local active cases – again, we are excluding the migrants here – are related to these five clusters.

During the first wave of the pandemic however between March and April, the only clusters which were found were restricted to households.  Measures which kept people inside also meant that asymptomatic and unknowing carriers of the virus transmitted it to less people.

Average number of tests double the average number in March and April

A significant part of Malta’s handling of the pandemic has been based on extensive testing. Malta has consistently placed well on the charts for the number of tests carried out in relation to its population.

However, comparing the average amount of tests carried out in the first wave against the current wave we can see that the average in the current wave far exceeds that in the first wave.

The number of tests carried out between 16 March and 21 April is 23,989 while the number of tests carried out from 23 July to the present day stands at 24,250 – a figure already exceeding that in the first wave even though the period being taken into consideration is some 20 days shorter.

On average, this translates to an average of 648 tests per day during the first wave and 1,347 tests per day in the current wave. 

It should be noted that while the number of tests per day has remained largely stable in the current wave, there were significant disparities in the first wave, with the period starting with between 250 and 300 tests per day in mid-March and ending with around 1,000 tests per day in mid-April.

2.81% of tests in last three days came back positive – above March to April average, but below peak

As said by health authorities time and time again, the more tests one carries out, the more likely they are to find positive cases.

If we look at the percentage of positive cases when compared to the number of tests carried out, we can see that that percentage is lower in the current wave than back in the first wave – possibly indicated that transmission of the virus now is less prevalent than it was back then.

The average percentage of tests which came back positive during the first wave was of 1.97%, while the current average for the current wave stands at 1.18%.

However, it should be noted that the same percentage over last weekend – between Friday and Sunday when a total of 143 cases were found – has increased to over double that average.

Indeed, the percentage of positive cases against the number of tests carried out increased to 2.85% on Friday, 2.58% on Saturday, and 3.01% on Sunday – a more worrying trend if it continues.

This is still not close to the peak of the first wave. At that wave’s peak, 52 cases from 825 tests were found on 7 April – equivalent to 6.3%. 

The positive rate was similarly high in the early stage of the pandemic – it averaged at 4.15% between 20 and 25 March, for instance, when cases were consistently in double digits and daily test numbers still in the 200 or 300 region.

Main difference in waves is in means of transmission

Some conclusions can be drawn from such an analysis.

Firstly, while the figures in terms of the number of cases are currently quite comparable – it is clear that if cases do continue to increase at the current rate, the number of new infections will far exceed those in the first wave.

It should be noted that the cases in the first wave peaked across three days – when 52 and 38 peak were found within three days of each other.  In the current wave however, the number of cases being found seems to be more sustained – the last three days have seen 49, 40, and 54 new cases respectively.

This is reflected in the percentage of tests which bring back a positive result, with that number being far above both the average for the rest of the wave and above the average of the whole first wave – and this being despite the increase in testing now compared with March and April.

The one major difference between the two waves has been the way in which transmission has occurred. 

While the first wave was largely characterised by imported cases and then sporadic cases of local transmission, a significant portion – almost half in fact – of the current wave can be attributed to specific clusters.

That is the symptom of perhaps the biggest variable when comparing the two scenarios: for the majority of the first wave, most establishments in Malta were closed; while today, all – save for dance floors and major mass events – remain open.