After a comparatively low number of Covid-19 cases, a slow uptick is noticed as more travellers land on Cambodian shores. But does the Kingdom have it all under control?
The country is bracing for the second phase of Covid-19 as the numbers creep up after a nearly 40-day hiatus. Beginning May 20, new cases made up of air travel arrivals from overseas pushed the toll up to 129 with no fatalities. Only three were hospitalised.
US Centres for Disease Control and Prevention Cambodia’s (US CDC) global health protection programme director Dr Michael Kinzer said: “It is a very small fraction so far, but we think this is typical of a second phase.
“It is what we were expecting from the second phase of the epidemic which is testing arriving passengers who are infected, controlling them, quarantining them, following their contacts, and making sure we stop transmissions.”
Unlike neighbouring countries, Cambodia’s borders were not closed per se, as air passengers trickled in mostly into Phnom Penh and via water transportations.
With travel restrictions easing around the world, Cambodian health authorities are on alert as thousands are expected in the coming months.
The government has imposed compulsory Covid-19 prerequisites on foreigners arriving in the country, including the possession of a minimum $50,000 health insurance, Covid-19-free health certificate and a $3,000 deposit for health checks.
Apart from that, an initial health system has been designed to screen and test arriving passengers in Phnom Penh, although this needs some adjusting to fit the current scenario.
“I think there are still a lot of questions that the government is trying to answer, including where the samples are tested, how the results are recorded, what tests are used, what percentage of passengers get tested, and how it is paid for,” Kinzer said.
He notes that every country in the world is going to be faced with these questions and no one is going to have the right answer.
“Therefore, Cambodia is now in the process of coming up with answers to those questions and I am sure they will have something. They will try, decide it does not work well enough, and they will try something else. Again, every country on earth is going to be faced with the same problems,” he said.
In the meantime, close cooperation with Cambodia Airports, and other agencies in the government stay on track so that they know what is coming.
“Because, if every passenger is going to be tested, whatever lab that is being used to test needs to know that suddenly they are going to get 500 samples.
“They would need to assign staff and prepare reagents. So there is a whole system that needs to be prepared to follow up on any kind of decision as to how we are going to screen arriving airline passengers,” he said.
An uptrend is already visible based on State Secretariat of Civil Aviation’s record where a 30 per cent increase was seen in aircraft movement and passenger arrivals within two weeks of June compared to the previous month.
Last month alone, 20,818 passenger arrivals were charted in all three airports in the Kingdom, with the capital’s airport receiving the highest number of 17,796 travellers.
In Preah Sihanouk, some 1,066 Chinese nationals comprising of workers and investors made their way there between May 23 and June 13, said provincial hall spokesman Kheang Phearum.
“Quarantine is quarantine”
Up to April 12, there were 122 cases in the Kingdom, most of them traced to someone who brought it in.
“Basically, you have a case that comes back and they have contacts or people who they were around with at that time. Those contacts who ended up being infected were mostly high-risk household contacts such as spouses and children,” said Kinzer.
Business partners or regular interlocutors fell into the medium-risk category while the low-risk group consists of anyone who was indoors with an infected person.
“The vast majority, even if high-risk contact, did not get infected. We can say that because we carried out contact tracing with every single case and we tracked over 2,200 contacts in total,” he said.
Still, the authorities are aware of the challenges as the system to screen and test passengers is only present at the Phnom Penh International Airport.
There are no laboratories to conduct testing outside the city. There are also few resources in Sihanoukville, even though arrivals are rising there.
For now, airline passengers are tested for Covid-19 upon arrival and ordered to self-quarantine for 14 days in their lodgings if they test negative before being re-tested on Day 13.
What if they breach the order by going out? Are their activities monitored?
“No. Quarantine means quarantine. They [must] stay home. Cambodia currently does not have the capacity to police self-quarantines,” Kinzer said, adding that the absence of monitoring might not necessarily cause problems but it is not ideal.
“A lot of what we do in Cambodia – because of resources and insufficient feasibility – is not ideal. There is no perfect system. Cambodia is a lower-middle-income country. It has to make choices as to how it uses its resources,” he said.
It is understood that earlier plans to put up travellers in additional hotels and other facilities to assist in quarantines were shelved, apart from 3,000 rooms presently available, as Cambodia did not have the resources to keep people in one place for two weeks due to the high pace in arrivals.
This makes the testing on Day 13 essential, including for those who are asymptomatic.
An asymptomatic infection acquired overseas or on a plane would most likely be picked up on arrival or during quarantine if symptoms develop or on the Day 13 test.
“We have had people who tested negative on arrival, and then positive on Day 13. [However] it is true that there have been asymptomatic transmissions, but we think it is in the minority of cases.
“The current system can detect cases and react quickly to track contacts and isolate them for testing,” he said.
“No surveillance is perfect”
To date, Cambodia has been somewhat fortunate, having recorded a negligible number of cases – a phenomenon that has elicited scepticism on the people’s susceptibility level.
In contrast, Thailand charted 3,135 cases as of June 17, Indonesia (41,431 cases) and Malaysia (8,515 cases).
However, Vietnam, which conducted mass testing, and Laos recorded comparatively small numbers and no deaths. Most of these countries imposed strict movement restrictions.
But with no evidence to support the small record in Cambodia, authorities are inclined to point to the fast action of the Cambodian government to ban mass gatherings, impose movement restrictions and quarantine at-risk populations, such as the returning migrant workers and garment workers.
The policies were said to have had direct impacts on transmission while stringent contact tracing took place.
“It sounds sort of technical, but it was an essential part of the response and one of the main reasons why we were able to stop [the virus] from entering the general population,” said Kinzer.
Still, it no cause to initiate mass testing at this point. The reason is also that they are incapacitated in doing so, not for the lack of test kits, but rather the capability to do so by the laboratories.
Even world-class testing facility Institut Pasteur du Cambodge (IPC) cannot test everybody although, during the peak with several clusters forming from end of February to April, it conducted 18,220 tests in 10 days.
“We could always be wrong but we don’t think there is community transmission until you know it is widespread. We might be missing a case or a cluster, but we are confident that we can handle that if it appeared,” he said.
No surveillance is perfect, and “we know ours is not perfect”, Kinzer contends. But the presence of Covid-19 in an immunologically naïve population, or a population that does not have resistance to disease, cannot go unnoticed.
“You would see it in many places and you would see severe cases. Even in the 125 or 126 cases we have had, none of them has been even moderate. They were mild cases.
“So for us, that is another piece of evidence that we are not seeing like the severe tip of an iceberg. Because if you think that you are only seeing the tip, you would be seeing the people who are dying or sick. So we haven’t seen that at all,” he said.
Studying the virus
Having said that, Kinzer hypothesised that Cambodia’s minimal number of air-conditioned malls, zero mass public transportation system such as subways, and an outdoor society could have removed any opportunity for people to be jammed together in close quarters.
“Cambodia is a fairly young population but we don’t have any evidence that young people are less prone to being infected. They just get less severe diseases. So there are a lot of ideas for why they don’t have it. It could all be true [but] I don’t think any of them is responsible for why we are protected,” he said.
What is certain, though, is the presence of IPC whose resources – the staff made up of world-class and multi-published scientists with a global network – continues to play a key role in testing and studying the samples.
Being one of 17 World Health Organisation (WHO) Covid-19 reference labs, IPC has been conducting tests before many countries in the world, which enabled the authorities to decide if someone was infected and act immediately on that information. In fact, they were the first in the region to get a test they could use regularly.
IPC is part of a working group involving WHO, National Institute of Public Health (NIPH), US CDC, Cambodia Communicable Disease Control Department (CCDC) and US-based National Institutes of Health (NIH).
In April, an article by the Southeast Asia Globe outlined behind-the-scenes efforts that spoke about the collaborative work led by NIH with IPC’s virology unit using IDSeq – an open-source software that allows scientists to log in pathogens in metagenomic sequencing data.
The scientists studied the samples by conducting a genome test on the virus and logging the data into IDSeq, which is part of a mass effort by scientists around the world to sequence and upload information about the virus.
Researchers Jessica Manning and Jenninfer Bohl from the National Institute of Allergy and Infectious Diseases’ Laboratory of Malaria and Vector Research in Phnom Penh, said genome sequencing’s main function was not to replace medical kits for widespread testing but to give a broader picture of how the virus is evolving and spreading.
The Globe wrote that the sequencing looks at how one could implement public health measures to stop the virus’ spread, not something that would be used as a basic diagnostic.
So far, the sequencing that has been done is to get the full gene of the virus, which is a different technique than just seeing whether a person is infected, Kinzer said.
It is not known if a new strain has been identified in the Cambodian context. However, a divergence of strain is invariably common if there was high transmission as the virus tends to mutate in such conditions as in the case of the Ebola epidemic in West Africa.
“In general, viruses want to become more infectious and less dangerous. This is good news for the general population, although that means we will have more cases, so we will have more work to do but I don’t know what the status is in Cambodia.
“Definitely around the world, we are seeing a divergence of strain. Some seem to have more virulence than others. For us, it does not matter. We do the same thing no matter what kind of strain you have. We try to stay focussed,” Kinzer said.
IPC could not be reached for comment on the possibility of a new strain.
With the research being carried out at the laboratories, in addition to the cooperation with CCDC where data sharing was made transparent and seamless, that segment seemed to move like clockwork.
“We did not see the same kind of resistance to rapid sharing of the results of confirmed cases that we saw in some other countries,” Kinzer said.
Specimen transport setback
Nevertheless, the make-up has yet to repair some quirks or setbacks such as the absence of a unified specimen transport network – meaning a system of cars and drivers that brings the specimens to the laboratory for testing.
There are disease-specific programmes for tuberculosis, malaria and HIV/AIDS, and non-governmental organisations with their systems, but all the variables are not coordinated.
This is the main barrier to Covid-19 samples being sent from the provinces, Kinzer said, adding that health officers have to use taxis or assign an ambulance, but that would deprive the people there of an ambulance.
“So we are trying to work with partners and the government to come up with some kind of coordinated system for specimen transport so that we can get the specimens tested quickly.
“Without that, we have less of an ability to confidently say what is going on in the provinces, and that is something necessary if we are going to talk about whether there is or is not community transmission. So specimen transport is a big challenge for us,” he said.
It also struggles with human resources shortages for routine public health work, particularly data entry which is crucial in charting the course of work.
“It sounds a little boring to outsiders, but it is essential for knowing what is going on and if what we are doing is making a difference. We are working with the NIPH to support their data systems which are not as resourced as IPC’s,” he said.
So what does the future hold?
Short answer, the team is confident of handling anything that mimics past scenarios.
Thus, despite having clusters and imported cases, the authorities are likely to manage them by isolating, tracing the contacts and preventing further transmissions.
“[However] we don’t have a [wholesome] system that can handle the levels of numbers of cases that we have seen in some of the harder-hit countries.
“There is still a lot of work to be done like at the provincial level [as] they will need to manage cases,” Kinzer said.
The team needs to also have a more robust data management system if it is going to manage hundreds of cases instead of dozens of cases.
“So, we still need to build on what we have. We need to prepare for the worst-case scenario because we don’t know. I smile because I don’t know what is going to happen,” he said.