Beating Covid curiosity

In a stunning upset which perhaps many did not see coming, Pakistan has managed to bring down its number of daily cases dramatically (down 50 percent since 15-July). Many associated this to reduced testing, but it seems the decline of the positivity rate to 6.6 percent (as on 26-July) stands in the range that satisfies the World Health Organization’s (WHO) benchmark of adequate testing. In another indicator that measures tests per confirmed cases, Pakistan is (now) well-within the range specified by WHO for adequate testing. For reasons that continue to baffle observers, Pakistan is flattening the curve.

Back in the 12th century, English theologian William hailing from a village Occam (or Ocham) proposed (what became known as the law of parsimony or “Occam’s razor” in philosophy), that the simplest of explanations are often the most likely. In other words, a hypothesis with the least number of assumptions is often one’s best bet. So, what is Occam’s razor in the curious case of declining Covid-19 cases in Pakistan?

Were the lockdowns effective, enough to reduce mobility and stopping the spread? Is there an inherent immunity amongst Pakistanis that restricted the spread? Has there been enough testing? Was the government contract tracing and isolating effectively? Were people socially distancing conscientiously, wearing masks, and washing hands every instance they touched an object?

Let’s look at each. Though businesses and educational institutes were closed down and travel was largely restricted, with the most recent lockdown taking shape in the form of shutting down 400 major hotspots identified by the government, mobility data from Google shows overall mobility across provinces has revived (read more details here: “Covid-19: Optimism vs evidence-II”, July 9, 2020), now coming up to pre-Covid levels. Cases since this recovery have continued to decline. Public spaces including educational institutes, cinemas, marriage halls, restaurants, and many offices are still closed but factories, construction sites, and public transport have re-opened.

Two things are of note here: the most recent lockdown did not lead to reduced mobility (as reflected in data) and daily cases started to reduce before the latest hotspot lockdown was instated and maintained its downward streak.

Until two weeks ago, Pakistan was testing way below WHO’s recommended level (50,000 tests per day) and had a pretty high positivity rate which indicated inadequate testing. Government ramped up testing between the first and third week of June—peaking at 31,000 on Jun-18 — after which daily testing started to come down. During this high testing period, both positivity rate and tests per confirmed cases were out of the WHO-identified ranges. The former was too high and the latter too low. It is also pertinent to mention here that only symptomatic cases were pursued and tested in government hospitals.

In terms of tracing, Pakistan has pursued a limited number of positive cases; not all. In fact, evidence suggests tracing was particularly done in the start when the virus first started spreading and stopped picking steam thereafter. Globally, technological interventions for contact tracing have been used to track cases, test and isolate but while this idea was presented to the government, it was never really adopted in the country. Whatever tracing Pakistan had done, it was not technologically driven and as a result, any tracing strategy in the country would be difficult to rank or evaluate.

Pakistanis may have high immunity to the virus, but this requires a mountain of empirical evidence to confirm and cannot be relied on right now. Lastly, that Pakistanis have been careful in wearing masks and adhering to Covid-safe practices cannot be proven either, though anecdotal evidence would suggest that the usage of masks has been closely administered.

Evidently, none of these reasons provide confirmed evidence for Pakistan’s sudden improvement in key indicators. Perhaps, they have all worked together in unison. That is the simplest explanation—the Occam’s razor. One can poke at numbers to discover inconsistencies, but a more productive course may be to think ahead and think of contingencies. In any case, until there is a cure, Pakistan or any country for that matter will not be in its final lap (Read: “Covid cure”, July 23, 2020). Therefore, a few cautions. One, folks should continue to wear masks and socially distance, during Eid and especially now that life is going back to normal. Two, they should test and isolate as soon as any symptoms develop, or a contact becomes positive. Third and most important, the government must not stop testing and tracing because its entire “hotspot” lockdown strategy is based on real-time data of confirmed cases. Reduced testing would essentially blindfold the government from implementing an effective smart lockdown.