Utilization of statins in patients with type 2 diabetes mellitus: the practice in a lower middle income South Asian country.

Background: Cardiovascular disease (CVD) is a major cause of morbidity and mortality among patients with type 2 diabetes. Statin reduces CVD risk. The ACC/AHA 2018 guideline on dyslipidemia recommends all patients with type 2 diabetes mellitus to be given moderate-intensity statin. We aimed to determine the prescription practices of statins among patients with type 2 diabetes mellitus. Methods: A cross-sectional study was conducted from February to April 2021. Patients with type 2 diabetes mellitus between 40 and 75 years were recruited from the University Medical Clinic and Endocrine Clinic at Colombo South Teaching Hospital, Sri Lanka. Results: Four hundred seventy-one patients were enrolled with a mean age of 59.05 (± 9.139) years. The mean duration of diabetes was 10.97 (± 9.57) years. Four hundred forty-one (93.6%) patients were on statin and 30 (6.4%) patients were not on statin therapy. Those not on statins were not prescribed statins. Conclusions: There were 163 (34.61%) patients who required high intensity. Though only 3 (1.73%) were on high-strength statin, the rest were on moderate (152, 93.25%), low (4, 2.45%), and none (4, 2.45%). Among patients with prior history of atherosclerotic cardiovascular disease (ASCVD) and the high-risk category according to the 10-year ASCVD risk estimation (155, 32.91%), only 17 (10.97%) have achieved optimal LDL therapeutic targets (55mg/dL). A large proportion of the study population received statin therapy for primary and secondary prophylaxis. However, the majority were on suboptimal doses of statin and have not achieved therapeutic targets with regard to LDL-C levels. The findings highlight the importance of improving statin therapy and optimizing lipid management according to evidence-based guideline recommendations.

Immune responses to Sinopharm/BBIBP-CorV in individuals in Sri Lanka.

As there are limited data of the immunogenicity of the Sinopharm/BBIBP-CorV in different populations, antibody responses against different SARS-CoV-2 variants of concern and T cell responses, we investigated the immunogenicity of the vaccine, in individuals in Sri Lanka. SARS-CoV-2-specific antibodies were measured in 282 individuals who were seronegative at baseline, and ACE2 receptor blocking antibodies, antibodies to the receptor-binding domain (RBD) of the wild-type (WT), alpha, beta and delta variants, ex vivo and cultured IFNγ ELISpot assays, intracellular cytokine secretion assays and B cell ELISpot assays were carried out in a sub cohort of the vaccinees at 4 and 6 weeks (2 weeks after the second dose). Ninety-five percent of the vaccinees seroconverted, although the seroconversion rates were significantly lower (p < 0.001) in individuals >60 years (93.3%) compared to those who were 20-39 years (98.9%); 81.25% had ACE2 receptor blocking antibodies at 6 weeks, and there was no difference in these antibody titres in vaccine sera compared to convalescent sera (p = 0.44). Vaccinees had significantly less (p < 0.0001) antibodies to the RBD of WT and alpha, although there was no difference in antibodies to the RBD of beta and delta compared to convalescent sera; 27.7% of 46.4% of vaccinees had ex vivo IFNγ and cultured ELISpot responses respectively, and IFNγ and CD107a responses were detected by flow cytometry. Sinopharm/BBIBP-CorV appeared to induce a similar level of antibody responses against ACE2 receptor, delta and beta as seen following natural infection.

Comparison of the immunogenicity of five COVID-19 vaccines in Sri Lanka.

To determine the antibody responses elicited by different vaccines against SARS-CoV-2, we compared antibody responses in individuals 3 months post-vaccination in those who had received different vaccines in Sri Lanka. Abs to the receptor binding domain (RBD) of the ancestral (wild type) virus (WT) as well as to variants of concern (VoCs), and ACE2 blocking Abs, were assessed in individuals vaccinated with Moderna (n = 225), Sputnik V (n = 128) or Sputnik light (n = 184) and the results were compared with previously reported data on Sinopharm and AZD1222 vaccinees. A total of 99.5% of Moderna, >94% of AZD1222 or Sputnik V and >70% of Sputnik light, >60% of Sinopharm vaccine recipients, had a positive response to ACE2 blocking antibodies. The ACE2 blocking antibody levels were highest to lowest was Moderna > Sputnik V/AZD1222 (had equal levels) > Sputnik light > Sinopharm. All Moderna recipients had antibodies to the RBD of WT, alpha and beta, while positivity rates for delta variant was 80%. The positivity rates for Sputnik V vaccinees for the WT and VoCs were higher than for AZD1222 vaccinees while those who received Sinopharm had the lowest positivity rates (<16.7%). The total antibodies to the RBD were highest for the Sputnik V and AZD1222 vaccinees. The Moderna vaccine elicited the highest ACE2 blocking antibody levels followed by Sputnik V/AZD1222, while those who received Sinopharm had the lowest levels. These findings highlight the need for further studies to understand the effects on clinical outcomes.

Persistence of immune responses to the Sinopharm/BBIBP-CorV vaccine.

BACKGROUND: To determine the kinetics and persistence of immune responses following the Sinopharm/BBIBP-CorV, we investigated immune responses in a cohort of Sri Lankan individuals. METHODS: SARS-CoV-2 specific total antibodies were measured in 20-39 years (n = 61), 40-59 years (n = 120) and those >60 years of age (n = 22) by enzyme-linked immunosorbent assay, 12 weeks after the second dose of the vaccine. Angiotensin-converting enzyme 2 (ACE2) receptor blocking antibodies (ACE2R-Ab), antibodies to the receptor-binding domain (RBD) of the ancestral virus (WT) and variants of concern, were measured in a sub cohort. T cell responses and memory B cell responses were assessed by ELISpot assays. RESULTS: A total of 193/203 (95.07%) of individuals had detectable SARS-CoV-2 specific total antibodies, while 67/110 (60.9%) had ACE2R-Ab. A total of 14.3%-16.7% individuals in the 20-39 age groups had detectable antibodies to the RBD of the WT and variants of concern, while the positivity rates of those ≥60 years of age was <10%. A total of 14/49 (28.6%) had Interferon gamma ELISpot responses to overlapping peptides of the spike protein, while memory B cell responses were detected in 9/20 to the S1 recombinant protein. The total antibody levels and ACE2R-Ab declined from 2 to 12 weeks from the second dose, while ex vivo T cell responses remained unchanged. The decline in ACE2R-Ab levels was significant among the 40-59 (p = .0007) and ≥60 (p = .005) age groups. CONCLUSIONS: Antibody responses declined in all age groups, especially in those ≥60 years, while T cell responses persisted. The effect of waning of immunity on hospitalization and severe disease should be assessed by long term efficacy studies.

Kinetics of immune responses to SARS-CoV-2 proteins in individuals with varying severity of infection and following a single dose of the AZD1222.

To characterize the IgG and IgA responses to different SARS-CoV-2 proteins, we investigated the antibody responses to SARS-CoV-2 following natural infection and following a single dose of AZD1222 (Covishield), in Sri Lankan individuals. The IgG and IgA responses were assessed to S1, S2, RBD, and N proteins in patients at 4 weeks and 12 weeks since the onset of illness or following vaccination. Antibodies to the receptor-binding domain of SARS-CoV-2 wild type (WT), α, ß, and λ and ACE2 (Angiotensin Converting Enzyme 2) receptor blocking antibodies were also assessed in these cohorts. For those with mild illness and in vaccines, the IgG responses to S1, S2, RBD, and N protein increased from 4 weeks to 12 weeks, while it remained unchanged in those with moderate/severe illness. In the vaccines, IgG antibodies to the S2 subunit had the highest significant rise (P < 0.0001). Vaccines had several-fold lower IgA antibodies to all the SARS-CoV-2 proteins tested than those with natural infection. At 12 weeks, the haemagglutination test (HAT) titres were significantly lower to the α in vaccines and significantly lower in those with mild illness and in vaccines to ß and for λ. No such difference was seen in those with moderate/severe illness. Vaccines had significantly less IgA to SARS-CoV-2, but comparable IgG responses those with natural infection. However, following a single dose vaccines had reduced antibody levels to the VOCs, which further declined with time, suggesting the need to reduce the gap between the two doses, in countries experiencing outbreaks due to VOCs.

Kinetics of immune responses to the AZD1222/Covishield vaccine with varying dose intervals in Sri Lankan individuals.

BACKGROUND: To understand the kinetics of immune responses with different dosing gaps of the AZD1222 vaccine, we compared antibody and T cell responses in two cohorts with two different dosing gaps. METHODS: Antibodies to the SARS-CoV-2 virus were assessed in 297 individuals with a dosing gap of 12 weeks, sampled 12 weeks post second dose (cohort 1) and in 77 individuals with a median dosing gap of 21.4 weeks (cohort 2) sampled 6 weeks post second dose. ACE2-blocking antibodies (ACE2-blocking Abs), antibodies to the receptor-binding domain (RBD) of  variants of concern (VOC), and ex vivo T cell responses were assessed in a subcohort. RESULTS: All individuals (100%) had SARS-CoV-2-specific total antibodies and 94.2% of cohort 1 and 97.1% of cohort 2 had ACE2-blocking Abs. There was no difference in antibody titers or positivity rates in different age groups in both cohorts. The ACE2-blocking Abs (p < .0001) and antibodies to the RBD of the VOCs were significantly higher in cohort 2 compared to cohort 1. 41.2% to 65.8% of different age groups gave a positive response by the hemagglutination assay to the RBD of the ancestral virus and VOCs in cohort 1, while 53.6%-90% gave a positive response in cohort 2. 17/57 (29.8%) of cohort 1 and 17/29 (58.6%) of cohort 2 had ex vivo interferon (IFN)γ ELISpot responses above the positive threshold. The ACE2-blocking antibodies (Spearman's r = .46, p = .008) and ex vivo IFNγ responses (Spearman's r = .71, p < .0001) at 12 weeks post first dose, significantly correlated with levels 12 weeks post second dose. CONCLUSIONS: Both dosing schedules resulted in high antibody and T cell responses post vaccination, although those with a longer dosing gap had a higher magnitude of responses, possibly as immune responses were measured 6 weeks post second dose compared to 12 weeks post second dose.

Immune responses following the first dose of the Sputnik V (Gam-COVID-Vac).

As the first dose of Gam-COVID-Vac, is currently used as a single dose vaccine in some countries, we investigated the immunogenicity of this at 4 weeks (327 naïve individuals). 88.7% seroconverted, with significantly lower seroconversion rates in those over 60 years (p = 0.004) and significantly lower than previously seen with AZD1222 (p = 0.018). 82.6% developed ACE2 receptor blocking antibodies, although levels were significantly lower than following natural infection (p = 0.0009) and a single dose of AZD1222 (p < 0.0001). Similar titres of antibodies were observed to the receptor binding domain of WT, B.1.1.7 and B.1.617.2 compared to AZD1222, while the levels for B.1.351 were significantly higher (p = 0.006) for Gam-COVID-Vac. 30% developed ex vivo IFNγ ELISpot responses (significantly lower than AZD1222), and high frequency of CD107a expressing T cells along with memory B cell responses. Although single dose of Gam-COVID-Vac was highly immunogenic, administration of a second dose is likely to be beneficial.

Antibody responses to Sinopharm/BBIBP-CorV in pregnant mothers in Sri Lanka.

BACKGROUND: There are limited data regarding the safety and immunogenicity of the Sinopharm/BBIBP-CorV vaccine in pregnancy. Therefore, we sought to investigate the antibody responses and maternal and fetal adverse events following this vaccine in pregnant mothers in Sri Lanka. METHODS AND FINDINGS: SARS-CoV-2 receptor binding domain (RBD) specific total antibodies and ACE2 blocking antibodies were measured by ELISA in pregnant mothers (n = 94) who received the vaccine in the first (n = 2), second (n = 57) and third (n = 33) trimester of pregnancy. Data regarding adverse events and fetal and maternal outcomes were obtained from the women once they delivered. No adverse maternal or fetal complications reported such as miscarriage, thrombotic events, hypertensive disorders, fetal death, preterm delivery, or congenital anomalies were reported. 58/94 (61.7%) had RBD binding antibodies and were found to be seropositive at the time of recruitment. All women seroconverted after the second dose and 31/36 previously uninfected women and 57/58 previously infected women gave a positive response to ACE2 blocking antibodies. The RBD binding antibody levels (p = 0.0002) and ACE2 blocking antibodies (p<0.0001) were significantly higher in previously infected individuals post-second dose compared to uninfected individuals. CONCLUSIONS: The Sinopharm/ BBIBP-CorV vaccine appeared safe and induced high seroconversion rates and ACE2 blocking antibodies in pregnant mothers in the second and third trimester in pregnancy. However, the RBD binding antibodies and ACE2 blocking antibodies post-second dose were significantly higher in previously infected pregnant mothers post-second dose, suggesting that two doses of the vaccine are likely to be less immunogenic in previously unexposed individuals.

Seroprevalence of SARS-CoV-2 Infection in the Colombo Municipality Region, Sri Lanka.

Background: As the Municipality Council area in Colombo (CMC) experienced the highest number of cases until the end of January 2021, in Sri Lanka, we carried out a serosurvey prior to initiation of the vaccination program to understand the extent of the SARS-CoV-2 outbreak. Methods: SARS-CoV-2 seropositivity was determined in 2,547 individuals between the ages of 10-86 years, by the Wantai total antibody ELISA. We also compared seroprevalence using the haemagglutination test (HAT) to evaluate its usefulness in carrying out serosurveys. Results: The overall seropositivity rate was 24.46%, while seropositivity by HAT was 18.90%. Although The SARS-CoV-2 infection detection rates by PCR were highest in the population between the ages of 20-60 years of age, there was no statistically significant difference in the seropositivity rates in different age groups. For instance, although the seropositivity rate was highest in the 10-20 age group (34.03%), the PCR positivity rate was 9.80%. Differences in the PCR positivity rates and seropositivity rates were also seen in 60-70-year-olds (8.90 vs. 30.4%) and in individuals >70 years (4.10 vs. 1.20%). The seropositivity rate of the females was 29.70% (290/976), which was significantly higher (p < 0.002) than in males 21.2% (333/1,571). Conclusions: A high seroprevalence rate (24.5%) was seen in all age groups in the CMC suggesting that a high level of transmission was seen during this time. The higher PCR positivity rates between the ages of 20-60 are likely to be due to increased testing carried out in the working population. Therefore, the PCR positivity rates, appear to underestimate the true extent of the outbreak and the age groups which were infected.

Immune Responses to a Single Dose of the AZD1222/Covishield Vaccine at 16 Weeks in Individuals in Sri Lanka.

Due to limited access to vaccines, many countries have only administered a single dose of the AZD1222, whereas the dosage intervals have increased ≥4 wk. We sought to investigate the immunogenicity of a single dose of vaccine at ≥16 wk postimmunization. Severe acute respiratory syndrome coronavirus 2-specific Abs in 553 individuals and Abs to the receptor-binding domain of the Wuhan virus (wild-type) and the variants of concern, angiotensin-converting enzyme 2 receptor blocking Abs ex vivo and cultured IFN-γ T cell (Homo sapiens) responses and B cell (H. sapiens) ELISPOT responses, were investigated in a subcohort. The seropositivity rates in those >70 y of age (93.7%) was not significantly different compared with other age groups (97.7-98.2; Pearson χ2 = 7.8; p = 0.05). The Ab titers (Ab index) significantly declined (p < 0.0001) with increase in age. A total of 18 of 69 (26.1%) of individuals did not have angiotensin-converting enzyme 2 receptor-blocking Abs, whereas responses to the receptor-binding domain of wild-type (p = 0.03), B.1.1.7 (p = 0.04), and B.1.617.2 (p = 0.02) were significantly lower in those who were >60 y. Ex vivo IFN-γ T cell ELISPOT responses were seen in 10 of 66 (15.1%), whereas only a few expressed CD107a. However, >85% had a high frequency of cultured IFN-γ T cell ELISPOT responses and B cell ELISPOTs. Virus-specific Abs were maintained at ≥16 wk after receiving a single dose of AZD1222, although levels were lower to variants of concern, especially in older individuals. A single dose induced a high frequency of memory T and B cell responses.

Kinetics of immune responses to the AZD1222/Covishield vaccine with varying dose intervals in Sri Lankan individuals.

BACKGROUND: To understand the kinetics of immune responses with different dosing gaps of the AZD1222 vaccine, we compared antibody and T cell responses in two cohorts with two different dosing gaps. METHODS: Antibodies to the SARS-CoV-2 virus were assessed in 297 individuals with a dosing gap of 12 weeks, sampled at 12 weeks post second dose (cohort 1) and in 77 individuals with a median dosing gap of 21.4 weeks (cohort 2) sampled 6 weeks post second dose. ACE2 receptor blocking antibodies (ACE2R-Abs), antibodies to the receptor binding domain (RBD) of the virus and variants of concern (VOC) and ex vivo T cell responses were assessed in a sub cohort. RESULTS: All individuals (100%) had SARS-CoV-2 specific total antibodies and 94.2% of cohort 1 and 97.1% of cohort 2 had ACE2R-blocking Abs. There was no difference in antibody titres or positivity rates in different age groups in both cohorts. The ACE2R-blocking Abs (p<0.0001) and antibodies to the RBD of the VOCs were significantly higher in cohort 2, compared to cohort 1. 41.2% to 65.8% of different age groups gave a positive response by the haemagglutination assay to the RBD of the ancestral virus and VOCs in cohort 1, while 53.6% to 90% gave a positive response in cohort 2. 17/57 (29.8%) of cohort 1 and 17/29 (58.6%) of cohort 2 had ex vivo IFNγ ELISpot responses above the positive threshold. The ACE2R-blocking antibodies and ex vivo IFNγ ELISpot responses at 12 weeks post-first dose, significantly correlated with levels 12 weeks post second dose (Spearman's r=0.46, p=0.008) and (Spearman's r=0.71, p<0.0001) respectively. CONCLUSIONS: Both dosing schedules resulted in high levels of antibody and T cell responses post vaccination, although those with a longer dosing gap had a higher magnitude of responses, possibly as immune responses were measured 6 weeks post second dose compared to 12 weeks post second dose.

Persistence of antibody and T cell responses to the Sinopharm/BBIBP-CorV vaccine in Sri Lankan individuals.

BACKGROUND: To determine the kinetics and persistence of immune responses following the Sinopharm/BBIBP-CorV, we investigated immune responses in a cohort of Sri Lankan individuals. METHODS: SARS-CoV-2 specific total antibodies were measured in 20-to-39 year (n=61), 40-to-59-year and those >60 years of age (n=22) by ELISA, 12 weeks after the second dose of the vaccine. ACE2 receptor blocking antibodies (ACE2R-Ab), antibodies to the receptor binding domain (RBD) of the ancestral virus (WT) and variants of concern, were measured in a sub cohort. T cell responses and memory B cell responses were assessed by ELISpot assays. RESULTS: 193/203 (95.07%) of individuals had detectable SARS-CoV-2 specific total antibodies, while 67/110 (60.9%) had ACE2R-Ab. 14.3% to 16.7% individuals in the 20 to 39 age groups had detectable antibodies to the RBD of the WT and VOC, while the positivity rates of those >60 years of age was <10%. 14/49 (28.6%) had IFN γ ELISpot responses to overlapping peptides of the spike protein, while memory B cell responses were detected in 9/20 to the S1 recombinant protein. The total antibody levels and ACE2R-Ab declined after 2 to 12 weeks from the second dose, while ex vivo T cell responses remained unchanged. The decline in ACE2R-Ab levels was significant among the 40 to 59 (p=0.0007) and ≥60 (p=0.005) age groups. CONCLUSIONS: Antibody responses declined in all age groups, especially in those >60 years, while T cell responses persisted. The effect of waning of immunity on hospitalization and severe disease should be assessed by long term efficacy studies.

Changing epidemiology of dengue in Sri Lanka-Challenges for the future.

BACKGROUND: Dengue infections are on the rise in Sri Lanka and are spreading to all areas in the country. Here, we discuss the changes in dengue epidemiology in Sri Lanka in relation to changes in age distribution, changes in seroprevalence rates over time, and possible reasons contributing to such changes. METHODS AND FINDINGS: Although the incidence of dengue increased 20-fold from the year 2000 to 2012 and a further 3-fold from 2012 to 2019, this increase is not reflected in a similar increase in the age-stratified seropositivity rates for dengue. For instance, the annual seroconversion rates were 0.76% in 2013 and 0.91% in 2017. The annual seroconversion rates in the 6 to 17 age group were 1.5% per year in 2003, 3.9% in 2013, and 4.1% in 2017. In addition, although a 13-fold increase in dengue was seen in those who were <19 years of age, a 52.4-fold increase was seen in the 40- to 59-year age group. The case fatality rates (CFRs) have similarly changed, with 61.8% of deaths occurring in those <19 years of age in the year 2000, while in 2012 to 2018, the highest CFR were seen in those who were aged 20 to 39 years. Although there has been a marked increase in the number of cases, the vector densities did not change during a 4-year period. The proportion of adult individuals experiencing a secondary dengue infection has also remained between 65% and 75% between the years 2004 and 2018. CONCLUSIONS: A change in the ratio of symptomatic to asymptomatic infections can give rise to changes in the reported incidence of dengue. In order to take an appropriate policy decision in dengue control activities, it would be important to study the changes in virus serotypes, vector dispersion, and densities. Further, the contribution of the rise in metabolic diseases to an increase in the symptomatic as well as more severe infections due to dengue is explored.

Immune responses to a single dose of the AZD1222/Covishield vaccine in health care workers.

Several COVID-19 vaccines have received emergency approval. Here we assess the immunogenicity of a single dose of the AZD1222 vaccine, at one month, in a cohort of health care workers (HCWs) (629 naïve and 26 previously infected). 93.4% of naïve HCWs seroconverted, irrespective of age and gender. Haemagglutination test for antibodies to the receptor binding domain (RBD), surrogate neutralization assay (sVNT) and ex vivo IFNγ ELISpot assays were carried out in a sub-cohort. ACE2 blocking antibodies (measured by sVNT) were detected in 67/69 (97.1%) of naïve HCWs. Antibody levels to the RBD of the wild-type virus were higher than to RBD of B.1.1.7, and titres to B.1.351 were very low. Ex vivo T cell responses were observed in 30.8% to 61.7% in naïve HCWs. Previously infected HCWs, developed significantly higher (p < 0.0001) ACE2 blocking antibodies and antibodies to the RBD for the variants B.1.1.7 and B.1.351. This study shows high seroconversion after one vaccine dose, but also suggests that one vaccine dose may be insufficient to protect against emerging variants.