Given Singapore’s global interconnectedness, we are fated to share in the world’s blessings and also its curses. Epidemics, be they viruses or antibiotic-resistant bacteria, rightly put the Singapore authorities on alert, wherever they may occur. Therefore, the outbreak of the Zika virus in Singapore was treated as the unfortunate manifestation of what was always a relative likelihood as opposed to a breach of Singapore’s health security. However, it was the spread of the virus that caught many of Singaporeans by surprise, with local transmissions of the virus increasing and the number of local clusters increasing. Does this signify a failure on Singapore’s part to effectively manage and control such outbreaks of contagious illnesses especially given our recognised efforts in combating SARS and H1N1 Flu in recent years? The answer is not as simple as it seems.      

 

The current efforts to combat Zika should not be too readily compared against our previous efforts in dealing with SARS in 2003 and the 2009 H1N1 Flu outbreak, Singapore’s war against pandemics have been modelled on the previous wars that it has fought, therefore to state that Singapore is unable to handle pandemics based on its current performance and previous accomplishments ignores the fundamental issue that not all infectious sicknesses are created equal and the spectrum encompassing how such sicknesses are transmitted is very large. Hence we should not view the current Zika outbreak as a reflection of Singapore’s poor preparation for such epidemics on the level as that of SARS, but rather against our longtime local foe, the dengue fever, which bears much more resemblance to Zika than SARS or other recent viral outbreaks. It also serves an important lesson to us that preparations against such outbreaks can never be watertight and despite long-time precautions, the ability of viruses to mutate and the Singapore’s interconnectedness with the world are reminders of the dangers and likelihood of a pandemic outbreak in Singapore.

 

Zika is not your average virus

 

The main differences between Zika and previous viral outbreaks in Singapore that are relevant for this piece, aside from the fact that fatality rates are significantly lower, is that the Zika virus is transmitted by mosquitoes and not human-to-human contact. Mosquitoes, acting as the vector for the Zika virus, are responsible for the formation of clusters. Therefore, it only takes one infected person to enter Singapore and the mosquitoes will do the rest, by biting the infected person and then other people, it transmits the virus across a population. Unlike the SARS epidemic where the solution was to cut off the sources of the virus; humans, by quarantining them, the solution here is not as simple.

 

Attempts to eliminate Zika transmissions are essentially attempts to eradicate the Aedes mosquito, the only vector of the Zika virus thus far. The Aedes mosquito however has proven very versatile in more ways than one, also having the dubious distinction of being the carrier of multiple viruses such as the Dengue virus and the Chikungunya virus. Dengue itself has been a thorn in the side of Singapore health authorities for many years

 

Zika, like Dengue and Chikungunya, are vector-borne diseases that are inherently harder to control as opposed to Air or Droplet-Borne Diseases such as various Influenza viruses that pass easily from human to human. Vector-borne diseases are problematic because the question of prevention boils down to curtailing the impact and ability of the vector to spread the disease. The strategy used in Singapore is vector control. Hence mosquito-fogging is rather common and government bodies such as the National Environmental Agency are given special powers to inspect personal properties and penalize owners if mosquito-breeding is found. Singapore’s progress in this area has been remarkable given its high urban density and the ability of the Aedes mosquito to thrive in such built-up areas. In recent years there have been outbreaks of Dengue Fever in various areas of Singapore, however none as large as to warrant severe countermeasures such as en-masse fogging. Thus when compared to Singapore’s fight with Dengue, Zika is not something that Singapore is totally unprepared for. However why is it that Singapore has been perceived by some to have failed to detect and properly manage the Zika virus thus far?

 

Why Zika is confounding Singapore?

 

Since the first local case of Zika was confirmed on 27th August 2016, there have been 342 cases in Singapore as of 14th September 2016. However to put this number into perspective, on the 18th of February 2016, the Ministry of Health released an estimate that unless immediate measures were taken to suppress the Aedes mosquito population, the number of Dengue cases in 2016 may exceed 30,000 which is higher than the record of 22,170 cases in 2013. The report attributed this to the El Niño weather phenomenon and the replacement of the DENV-1 virus serotype with the DENV-2 virus serotype as the dominant virus, which has historically been associated with a sharp rise in Dengue cases. Currently for the week ending on the 10th of September, there have been 242 Dengue cases, not too far off the rise in Zika, keeping in mind both use the same vector.

 

Perhaps Zika is boosted by this perfect storm, where the vector for its spread is also experiencing a boost in numbers. Most Singaporeans would attest to the hardiness of mosquitos, having suffered their presence when outdoors. Nonetheless the fact that measures are in place to eradicate the same vector for Zika as Dengue; the Aedes mosquito, might suggest that such measures are, despite their success so far, still inadequate in preventing the spread of Zika?

 

The interesting thing about Zika is that it is not a “new” virus that recently jumped over from its origin point, apparently Zika has been around since the 1960s and the Ministry of Health has been aware of that. Dr Hoe Nam Leong, an infectious disease specialist, speaking to the Center for Infectious Disease Research and Policy, stated that:

 

“The laboratories in Ministry of Health and Ministry of Environment have been doing surveillance on this illness for several years, and we have not isolated Zika in patients or in mosquitoes… We suspect a significant mutation occurred that conferred [the virus] an advantage in spreading from person to mosquito to person. Previously, reports of Zika are far and few in between.”

 

 

Furthermore the strain of Zika in Singapore has been identified as a separate strain from that plaguing Brazil and the Americas which further boggles experts as to how this strain has suddenly arisen in Singapore, with speculation that it has mutated to a form that has become more readily transmissible among the urban population.

 

What can Singapore do now?

 

Given that the entry of Zika into Singapore was a matter of time given our status as a global hub for transportation and general interconnectedness with the global economy, the focus is now on preventing its spread within the city-state. Spot-checks on potential mosquito-breeding sites have been stepped up by the National Environmental Agency and in March 2016, the National Environmental Agency initiated the practice of implementing a $200 fine for homeowners if mosquitoes were found breeding on the premises, regardless of whether the property was in a dengue cluster or not, this is part of its regulatory powers which it has broadened in a bid to prevent the spread of vectors in the community. Outreach programmes have been stepped up in many constituencies, with phrases such as the “10 Minute Mozzie Wipeout” becoming familiar across many neighbourhoods in Singapore. Thus programmes that are already visible yearly have been given greater impetus in light of the Zika outbreak. Therefore it seems that whatever that can be humanely done is being done given current resources has already been done. Nonetheless there are several more ideas that are currently being tested or worth being implemented that could enhance Singapore’s preparedness.

 

There have been criticisms that construction sites, given the large amount of materials lying about, are key breeding sites for mosquitos. This notion was boosted when news broke that a Zika cluster had formed around the construction site of Sims Urban Oasis, leading to 37 reported cases among constructive workers on-site. However in Parliament, the Minister for the Environment and Water Resources Masagos Zulkifli stated that during recent checks in the first half of 2016, half the total mosquito-breeding habitats found were in homes, while only 5 per cent were at construction sites. It should also be noted that the National Environmental Agency possesses the power to issue Stop-Work Orders for construction sites that are found to be breeding mosquitoes and enforces this stringently.

 

 

However the question here becomes one of effectiveness, how effective are such spot-checks and are there easier ways to detect and destroy mosquito breeding sites? Fogging is a common remedy for this situation, however the high urban density of Singapore makes fogging difficult especially for high-rise residences that might be out of reach. Furthermore fogging might become too expensive given the size of urban residences and the frequency of such fogging might be too high for sustainable expenditure given that mosquitoes breed at a fast rate.

 

The National Environmental Agency, in a bid to find an easier solution to the problem, has embarked upon a pilot test project to release male Wolbachia-carrying Aedes aegypti mosquitoes into the environment. The Wolbachia bacteria prevents successful reproduction between Aedes mosquitoes with the result that after male Wolbachia-carrying Aedes mosquitoes mate with female Aedes mosquitoes without Wolbachia, their resulting eggs will not hatch. Though environmentalist have raised concerns over the impact of such a project on the environment, the project is being conducted under guidelines issued by the World Health Organisation and the National Environmental Agency has declared that this “mosquito suppression strategy is species-specific. Release of male Wolbachia-Aedes aegypti will only impact the Aedes aegypti population in the field, and not other insects.”

 

Therefore concerns that the current response to Zika is insufficient is simply unwarranted because of the nature of the Zika virus, how it is transmitted and how such transmission is cut. Personally I do not think that the current Zika outbreak reflects the inability of the authorities to respond to pandemic outbreaks. One has to look no further than the government’s response plan to influenza outbreaks in Singapore.

 

Controlling Infectious Diseases in Singapore

 

Zika, for all its concerns over its transmission by mosquitoes and its ability to cause microcephaly in newborns, is nothing compared to other viruses that Singapore has seen, the SARS outbreak in 2003 killed 33 people out of 283 infected while the H1N1 outbreak in 2009 killed 18 people, Zika by comparison has not proven fatal in Singapore yet. The economic fallout of such viruses is much higher since prevention is effected by reduced human contact necessitating the closure of schools such as in 2003 and 2009 and discouraging people from going to crowded places. All this places a toll on the economy by disruption of daily routines and business. Be too slow to effect such precautions and the disease might become entrenched in the community and prove harder to remove, however jump the gun too early and you might create economic disruption in the absence of an ascertainable viral threat, affecting both the economy and public confidence. Therefore when certain netizens began questioning why the news of Zika’s spread in Singapore was only released when nearly 40 cases were reported, the dilemma between maintaining public confidence and preventing unnecessary escalation of tensions within society came to the forefront. Thankfully since then, daily reports of Zika have emerged, which has led to praise by the World Health Organisation with its Outbreaks and Emergencies Head Peter Salama highlighting Singapore’s progress in tracking and containing the spread of the Zika virus and that “[w]e really have to congratulate the transparency and quick reporting the Government of Singapore has implemented in the case of this outbreak and hope that all other countries can do the same."

 

The measures that Singapore has taken to combat Dengue and Zika so far are hardly the limits of its arsenal. A key piece of legislation in Singapore is the Infectious Disease Act which gives tremendous power to the Director of Medical Services to order the medical examination and treatment of any person suspected to be a carrier or contact of an infectious disease and also prohibit meetings and public entertainment to combat the spread of any infectious disease. This is merely part of the large machinery that our health services possess in order to prevent the spread of infectious diseases and the government has not been afraid to enforce these responsibilities. In September 2016, a man was jailed for absconding from mandatory tuberculosis treatment in Tan Tock Seng Hospital's Communicable Disease Centre. The Ministry of Health has also come up with the MOH Pandemic Readiness and Response Plan for Influenza and other Acute Respiratory Diseases and continues to update the plan, the last being in 2014.

 

Thus the machinery to implement effective management of epidemics in Singapore does exist, however the main concern is not whether Singapore can effectively wield it as we have already demonstrated in the past, but whether we are able to anticipate and adjust our efforts to evolving pandemics. The SARS outbreak was a watershed moment, not just for Singapore but for the entire world in learning how to deal with influenza viruses, thereby allowing for a more effective management of the H1N1 virus. It is fortunate that this time round, Singapore’s efforts in combating Dengue have allowed the city-state to intensify instead of laboriously duplicating its efforts to deal with Zika.

 

Moving Forward

 

Therefore Singapore is prepared on the medical front, to fight the last war. However the nature of such pandemics is that they are constantly evolving and mutating and no new virus or bacteria is quite like the other. For instance, the Zika virus has the additional nasty suspected effect of causing microcephaly in unborn babies. However the Zika virus does raise the question of how Singapore will deal with future deadlier vector-borne diseases; perhaps a virus that is just as deadly as SARS but transmitted by mosquitoes instead of human-to-human contact. Given that experts have recently expressed skepticism at the prospect of completely eliminating the Aedes mosquito, complete eradication of such vector-borne diseases seems an unlikely proposition.  Therefore Singapore’s current efforts against Zika are fair given that mosquitoes have proven a consistent scourge of mankind that have survived all efforts thus far to eradicate them. Ultimately with all new infections, the initial spread will cause confusion and fear and Zika is no different. The main issue now for Singapore to adopt a level-headed response that attempts to determine how to further improve its efforts in combating vector-borne diseases while Zika’s non-lethality allows us to, however the next infection may not be so kind.