The World Health Organization in its interim guidance in March recommended temperature checks, the release of detainees and elimination of visits to prepare, prevent and possibly control the coronavirus 2019 (COVID-19) in prisons. Additional considerations include (i) the reduction of the prison population; (ii) non-shared accommodation; (iii) systematic screening of new prisoners; (iv) designation of hospitals; (v) robust health arrangements for prisoners with non-COVID illnesses; (vi) brief psychological interventions concerning anxiety for the prisoners and their family and (vii) parity of access to novel treatments for prisoners as they are considered a vulnerable population. A recent article in this journal has also noted preventive contract tracing measures for possible implementation in prisons. It is to be asserted here that the application of these to certain countries—especially the developing ones such as the Philippines—is extra difficult. Not only the application but also the determination of vulnerability can be pushed to the extreme.The case of the Philippines is particularly challenging and perhaps psychologically precarious to think about since it ‘has the highest jail occupancy in the world’. Early reports show several inmates and staff in the Philippines’ overcrowded prisons have tested positive. As of June 2020, there are more than 700 inmates who tested positive and given the ‘locked away’ nature of their condition, with a shortage of resources and non-allegiance to minimum health standards, the inmates and detainees ‘are the hidden victims of the COVID-19 pandemic’ and therefore ‘invisibly vulnerable’. Oftentimes, the reasons for hidden health hazards can lead to intricate mental issues that correlate with suicide ideation. Moreover, there are unreported deaths due to COVID-19, which need more attention because ‘social distancing was impossible inside the jail, prisoners lacked nutritious food, and that only about a quarter of the prisoners were wearing face masks’.This is despite the glaring data that there is a ‘drastic increase in prison population and incarceration rate’ from the early 2000s to 2019. In the years 2013–14, firsthand experiences of the author from weekly visits to one of the jails in Metropolitan Manila can attest how the congestion among the partitioning of prisoners is conspicuous. It continued to congest over the years. Now that visitation privileges are suspended, if not rarely and controllably allowed in minimal special cases, this creates a psychological impact for the prisoners and their families. And this ripples through as a public health case as it is ‘a matter of life and death not only for the detainees but for the public as well’.What the pandemic uncovers—even in prison—is ‘the existence of underlying unfair social and economic structures that are tightly bound to unfair health outcomes’. The elderly in prisons, as well as those with ‘pre-existing medical conditions (high blood pressure, heart diseases, respiratory tract diseases, cancer or diabetes), are more vulnerable to TB as well as the coronavirusCOVID-19 pandemic’. The elderly in prisons are considered ‘marginalized and vulnerable’ in society, so that partition management or transfer to designated hospitals are recommended prevention measures. Bachelet, U.N. High Commissioner for Human Rights, categorized jail inmates as ‘extremely vulnerable populations’ behind bars whose name can be substantially coined as ‘extreme vulnerability’.Interventions from the government include setting up a COVID-19 care facility at a prison and reducing the prison population. In July, over 15 000 inmates—those with light offenses and elderly—were released to decongest a disconcerting 534% capacity of the 467 jails nationwide. However, even with the reduction of population, the cumulative incidence rate, in epidemiological terms, might not be reduced to a substantial percentage. Moreover, Philippine jails and prisons are still at the risk of disasters, particularly natural and other hazards. Although extreme measures are yet to be arranged to be at par in confronting the extremely vulnerable condition, a preliminary psychological intervention can, in conclusion, (i) fund more computer units and facilities for the ‘e-dalaw’ (‘electronic prison visit’) program via Skype, (ii) expedite the release of similar or related cases with light offenses, (iii) attend to spiritual needs of the prisoners via virtual worship services, (iv) more careful assignations of mental health workers in the COVID-19 care facility and (v) regularly checked health regimens.