The epidemiology of COVID-19 in ten Southeast Asian countries

INTRODUCTION

Periodic benchmarking of the epidemiology of COVID-19 in the Association of Southeast Asian Nations (ASEAN) countries is critical for the continuous understanding of the transmission and control of COVID-19 in the region. The incidence, mortality, testing and vaccination rates within the ASEAN region from 1 January 2020 to 15 October 2021 is analysed in this paper.

METHODS

COVID-19 data on cases, deaths, testing, and vaccinations were extracted from the Our World in Data (OWID) COVID-19 data repository for all the ten ASEAN countries. Comparative time-trends of the epidemiology of COVID-19 using the incidence rate, cumulative case fatality rate (CFR), delay-adjusted case fatality rate, cumulative mortality rate (MR), test positivity rate (TPR), cumulative testing rate (TR) and vaccination rate was carried out.

RESULTS

Over the study period, a total of 12,720,661 cases and 271,475 deaths was reported within the ASEAN region. Trends of daily per capita cases were observed to peak between July and September 2021 for the ASEAN region. The cumulative case fatality rate (CFR) in Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand, and Vietnam, was of 0.9% (N=68), 2.2% (N=2,610), 3.5% (N=142,889), 0.1% (N=36), 1.2% (N=27,700), 4.0% (N=18,297), 1.6% (N=40,424), 0.1% (N=215), 1.7% (N=18,123), and 2.6% (N=21,043), respectively. CFR was consistently highest between January-June 2020. The cumulative mortality rate (MR) was 9.5, 13.7, 51.4, 0.2, 80.3, 32.4, 34.5, 1.6, 23.9 and 19.7 per 100,000 population, respectively. The cumulative test positivity rate (TPR) was 8.4%, 16.9%, 4.6%, 7.5%, 11.1%, 12.9%, 0.5%, 11.7%, and 3.6%, with the cumulative testing rate (TR) at 25.0, 90.1, 27.4, 917.7, 75.8, 177.8, 3303.3, 195.2, and 224.9 tests per 1,000 population in Cambodia, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand, and Vietnam, respectively. The percentage of population that completed vaccinations (VR) was 44.5%, 65.3%, 18.5%, 28.2%, 61.8%, 6.8%, 19.2%, 76.8%, 22.7%, and 10% in Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand, and Vietnam, respectively.

CONCLUSION

In 2020, most countries in ASEAN had higher case fatality rates but lower mortalities per population when compared to the third quarter of 2021 where higher mortalities per population were observed. Low testing rates have been one of the factors leading to high test positivity rates. Slow initiation of vaccination programs was found to be the key factor leading to high incidence and case fatality rate in most countries in ASEAN. Effective public health measures were able to interrupt the transmission of this novel virus to some extent. Increasing preparedness capacity within the ASEAN region is critical to ensure that any future similar outbreaks can be dealt with collectively.

Battling COVID-19 pandemic waves in six South-East Asian countries: A real-time consensus review

INTRODUCTION

COVID-19 has caused unprecedented public health concerns, triggering an escalated burden to health systems worldwide. The pandemic has altered people's living norms, yet coherently escalating countries' socioeconomic instability. This real-time consensus review aims to describe the epidemiological trends of COVID-19 pandemic across six South-East Asian nations, and countryspecific experiences on pandemic preparedness, responses and interventions.

METHODS

Consensus-driven approach between authors from the six selected countries was applied. Country specific policy documents, official government media statements, mainstream news portals, global statistics databases and latest published literature available between January-October 2020 were utilised for information retrieval. Situational and epidemiological trend analyses were conducted. Country-specific interventions and challenges were described. Based on evidence appraised, a descriptive framework was considered through a consensus. The authors subsequently outlined the lessons learned, challenges ahead and interventions that needs to be in place to control the pandemic.

RESULTS

The total number of people infected with COVID-19 between 1 January and 16 November 2020 had reached 48,520 in Malaysia, 58,124 in Singapore, 3,875 in Thailand, 470,648 in Indonesia, 409,574 in Philippines and 70,161 in Myanmar. The total number of people infected with COVID- 19 in the six countries from January to 31 October 2020 were 936,866 cases and the mortality rate was 2.42%. Indonesia had 410,088 cases with a mortality rate of 3.38%, Philippines had 380,729 cases with a mortality rate of 1.90%, Myanmar had 52,706 cases with a mortality rate of 2.34%, Thailand had 3,780 cases with a mortality rate of 1.56%, Malaysia had 31,548 cases with a mortality rate of 0.79%, and Singapore had 58,015 cases with a mortality rate of 0.05% over the 10- month period. Each country response varied depending on its real-time situations based on the number of active cases and economic situation of the country.

CONCLUSION

The number of COVID-19 cases in these countries waxed and waned over the 10-month period, the number of cases may be coming down in one country, and vice versa in another. Each country, if acting alone, will not be able to control this pandemic. Sharing of information and resources across nations is the key to successful control of the pandemic. There is a need to reflect on how the pandemic affects individuals, families and the community as a whole. There are many people who cannot afford to be isolated from their families and daily wage workers who cannot afford to miss work. Are we as a medical community, only empathising with our patients or are we doing our utmost to uphold them during this time of crisis? Are there any other avenues which can curb the epidemic while reducing its impact on the health and socio-economic condition of the individual, community and the nation?

Stabilization of Polar Nanoregions in Pb-free Ferroelectrics

The formation of polar nanoregions through solid-solution additions is known to enhance significantly the functional properties of ferroelectric materials. Despite considerable progress in characterizing the microscopic behavior of polar nanoregions (PNR), understanding their real-space atomic structure and dynamics of their formation remains a considerable challenge. Here, using the method of dynamic pair distribution function, we provide direct insights into the role of solid-solution additions towards the stabilization of polar nanoregions in the Pb-free ferroelectric of Ba(Zr,Ti)O_{3}. It is shown that for an optimum level of substitution of Ti by larger Zr ions, the dynamics of atomic displacements for ferroelectric polarization are slowed sufficiently below THz frequencies, which leads to increased local correlation among dipoles within PNRs. The dynamic pair distribution function technique demonstrates a unique capability to obtain insights into locally correlated atomic dynamics in disordered materials, including new Pb-free ferroelectrics, which is necessary to understand and control their functional properties.

An unusual cause of food-induced anaphylaxis in mothers

BACKGROUND

Galacto-oligosaccharides (GOS) are prebiotics added to commercial milk formula of infants and mothers. In recent years, cases of allergy related to GOS in atopic children have been reported in the South East Asian region.

CASE PRESENTATIONS

We describe a series of pregnant (n = 4) and lactating mothers (n = 2) who developed anaphylactic reactions after consumption of maternal milk formula containing GOS. All six subjects had pre-existing atopy and a positive skin prick test to GOS and 5/5 of the subjects who were tested had positive basophil activation tests to GOS. All of the mothers and their babies had normal neonatal outcomes after the reactions.

CONCLUSIONS

The supplementation of GOS into milk and beverages in the Asian region should take into account the rare chance of allergenicity of GOS in the atopic population.

Strain incompatibility and residual strains in ferroelectric single crystals

Residual strains in ferroelectrics are known to adversely affect the material properties by aggravating crack growth and fatigue degradation. The primary cause for residual strains is strain incompatibility between different microstructural entities. For example, it was shown in polycrystalline ferroelectrics that residual strains are caused due to incompatibility between the electric-field-induced strains in grains with different crystallographic orientations. However, similar characterization of cause-effect in multidomain ferroelectric single crystals is lacking. In this article, we report on the development of plastic residual strains in [111]-oriented domain engineered BaTiO(3) single crystals. These internal strains are created due to strain incompatibility across 90° domain walls between the differently oriented domains. The average residual strains over a large crystal volume measured by in situ neutron diffraction is comparable to previous X-ray measurements of localized strains near domain boundaries, but are an order of magnitude lower than electric-field-induced residual strains in polycrystalline ferroelectrics.

Polarized neutron diffraction at a spallation source for magnetic studies

The availability of high-power spallation neutron sources, along with advances in the development of coupled moderators and neutron polarizers, has made it possible to use polarized neutrons on time-of-flight diffractometers forin situstudies of phenomena contributing to field-induced magnetization of a material. Different electronic and structural phenomena that contribute to the overall magnetization of a material can be studied and clearly identified with polarized neutron diffraction measurements. This article reports the first results from polarized neutron diffraction experiments on a time-of-flight instrument at a spallation source. Magnetic field-induced rotation of electron spins in an Ni–Mn–Ga single crystal was measured with polarized neutron diffraction at the MAGICS reflectometer at the Spallation Neutron Source at Oak Ridge National Laboratory. The difference in intensities measured with spin-up and spin-down polarized neutrons is proportional to the field-induced magnetization of the crystal. The polarized neutron measurements indicate that the magnetic form factor for the 3delectrons of Mn in Ni–Mn–Ga is lower than the value reported earlier for an ideal spherical symmetry of electronic distribution. Future experiments for studying field-induced magnetization in materials following the current methodology are outlined.

Lattice parameter determination using a curved position-sensitive detector in reflection geometry and application to Smx/2Ndx/2Ce1–xO2–δceramics

X-ray diffractometers with curved position-sensitive (CPS) detectors have become popular for their ability to perform fast data collection over a wide 2θ range, enabling kinetics studies of chemical reactions and measurement of other time-resolved solid-state phenomena. While the effect of sample displacement onhkl-specific apparent lattice parameters has been explored for a transmission-mode Debye–Scherrer geometry, such effects for a reflection-mode Debye–Scherrer geometry are not yet well understood. The reflection-mode Debye–Scherrer geometry for CPS detectors is unique in the sense that the angle for the incident X-ray beam is kept fixed with respect to the normal of a flat diffracting sample, while the diffracted beams are measured at multiple angles with respect to the sample normal. An efficient method for precise lattice parameter determination using linear extrapolation of apparent lattice parameters calculated from differenthkldiffraction peaks is proposed for such geometries. The accuracy involved with this method is investigated for an Si powder standard. The extrapolation method is then applied to develop an empirical relationship between composition (x) and the lattice parameter (ao) of Smx/2Ndx/2Ce1−xO2−δceramics for solid oxide fuel cell electrolytes. In this system, the empirical relationship betweenxandaois compared with a previous theoretical prediction.