The recent spike in the number of COVID-19 cases has been attributed to cluster spread from an infected person to family members or to individual in the same household or same address, prevalently in Central Trinidad.
Using a series of comparative data, derived from maps and graphs, during his presentation at Wednesday’s virtual COVID-19 press conference, manager of the Ministry of Health’s Geographic Information System (GIS) unit, Roshan Seeramsingh said that the county of Caroni has recorded the highest number of cases, though there were less cases in Epidemiological Week 11 (March 14-20) when compared to the other weeks of the year thus far.
He said in comparing the spread of the virus in the month of February, where less communities recorded positive cases, to the month of March, the data would show that whereas during Epidemiological Weeks 6 and 7, represented by the periods February 7-13 and February 14-20, respectively, the highest number of cases was six, Epidemiological Weeks 10 and 11 covering the periods March 7-13 and March 14-20, respectively, recorded a high of 16 cases in any given area.
“We see that not only are more areas affected but the number of cases in many of these areas would have also increased.
“We see that that general Chase Village, Carapichaima, Balmain areas, those areas are hot areas, areas that would have recorded a high number of cases and these are areas we need to look at.”
Seeramsingh said that using the criteria of a minimum of three cases within a one-kilometre search distance, the determination of spatial clusters and their relevant maps were derived, with each map representing a two-week period.
He said looking back at Epidemiological Weeks 4 and 5, covering the periods January 24-Feb 6, and Epidemiological Weeks 6 and 7, covering the period Feb 7-20, what the country experienced during Epi Weeks 4 and 5 was a significant number of clusters.
“In fact there were 11 clusters at that point in time with six of these clusters being recorded in that Port of Spain to El Dorado area.”
He said of the other five, one was in East Trinidad, two in Chaguanas, and two around the San Fernando area.
“If we look at Epidemiological Weeks 6 and 7, we saw the number of clusters decrease significantly to three; one in Chaguanas, one in San Fernando, and one in the Diego Martin area,” Seeramsingh said, and added that despite the decrease in the number of clusters, both Chaguanas and San Fernando maintained at least one cluster each.
He noted that in Epidemiological Weeks 8 and 9 (February 21-March 6) there were only two clusters, a decrease compared to Epi Weeks 6 and 7, with the same two areas, Chaguanas and San Fernando recording clusters again, while in Epi Weeks 10 and 11 a significant increase was recorded, with the number of clusters jumping from two to 10, of which six were from Central Trinidad.
“There would have been a dip in the number of cases, and there was a subsequent increase during Epi Weeks 10 and 11, during which one cluster recorded 11 cases of the virus, the highest number of cases within any cluster.”
Seeramsingh stated that the maximum number of cases within any family, or at the same home or same address, would have range between three to six cases but what was interesting to note was the total cases within the clusters which were linked to persons either in the same family or at the same home or same address.
He added that during Epidemiological Weeks 4 and 5, 21 out of the 42 cases would have been linked to someone else at the same home or at the same address, while in Epidemiological Weeks 6-7, all 12 persons identified in clusters were linked to someone within the home.
“In Epidemiological Weeks 8 and 9, eight out of the 10 cases identified within clusters were linked to someone else within the home. As we look at Epi Weeks 10 and 11, we see that 33 out of the 43 persons who were identified as persons with clusters were linked to someone else within the family or at the same home or at the same address.
Stating that the numbers are still significantly high, Seeramsingh said: “We don’t want this to get to a point where it continues to expand, and we want to continue to practice our measures as have been put in place and we’ve practiced in the past, so that this doesn’t get out of hand.
Index cases impact
Seeramsingh said on Saturday the country had 12 index cases (infected persons), 23 primary contacts that turned positive, and eight secondary contacts that turned positive, for a total of 43 cases, however, when compared with the most recent data, there are 21 index cases, 31 primary contacts, and 10 secondary contacts, for a total of 62, which represent an increase in all three categories.
He said the majority of the increase was recorded in County Caroni.
Seeramsingh also shared that the Ministry of Health has gone live with its new COVID-19 GIS Dashboard.
Members of the public can visit the dashboard via the Ministry of Health’s website, health.gov.tt, to get access to COVID-19 statistics and charts.