Reinfection rates, change in antibody titers and adverse events after COVID-19 vaccination among patients previously infected with COVID-19 in Metro Manila, Philippines: a secondary analysis of a completed cohort study.

BACKGROUND: Variation in immune response to COVID-19 vaccines is observed among different ethnicities. We aimed to describe the reinfection rates, change in antibody titers, and adverse events among Filipinos. METHODS: This is a secondary analysis of a cohort study of 307 participants within one year of having COVID-19 infection. We measured COVID-19 antibody levels at pre-determined timepoints (Days 21, 90, 180, 270, and 360 from initial infection). We monitored for COVID-19 symptoms and obtained details on COVID-19 vaccination. An adjudication committee classified the participants as probable, possible, or unlikely COVID-19 reinfection. We determined the probable reinfection rate, adverse events, and the geometric mean titer (GMT) ratio of pre- and post-vaccination antibody levels according to type and brand of COVID-19 vaccine. RESULTS: At the end of the follow-up period, 287 (93.5%) out of 307 study participants were fully vaccinated, 1 was partially vaccinated (0.3%), and 19 were unvaccinated (6.2%). Among the fully vaccinated participants, those given mRNA vaccines had the lowest reinfection rate (19.2 cases/100 person-years, 95% CI 9.6, 38.4), followed by viral vector vaccines (29.8 cases/100 person-years, 95% CI 16.9, 52.4). We observed the highest reinfection rate among those given inactivated virus vaccines (32.7 cases/100 person-years, 95% CI 23.6, 45.3). The reinfection rate was 8.6 cases/100 person-years (95% CI 4.1, 17.9) for unvaccinated participants and 3.6 cases/100 person-years (95% CI 0.5, 25.3) for partially vaccinated participants. We observed the largest rise in antibody titers among those given mRNA vaccines (GMT ratio 288.5), and the smallest rise among those given inactivated virus vaccines (GMT ratio 16.7). We observed the highest percentage of adverse events following immunization with viral vector vaccines (63.8%), followed by mRNA vaccines (62.7%), and the lowest for inactivated virus vaccines (34.7%). No serious adverse events were reported. CONCLUSION: Vaccinees given the mRNA vaccines had the lowest reinfection rate and the highest rise in antibody titers. Vaccinees given inactivated virus vaccines had the highest reinfection rate, smallest rise in antibody titers, and lowest percentage of adverse events. The small sample size and imbalanced distribution of the type of vaccines received limits the external generalizability of our results. STUDY REGISTRATION: The cohort study was registered at the Philippine Health Research Registry on December 14, 2020 (PHRR201214-003199).

Durability and extent of protection of SARS-CoV-2 antibodies among patients with COVID-19 in Metro Manila, Philippines.

Introduction: Information on the magnitude and durability of humoral immunity against COVID-19 among specific populations can guide policies on vaccination, return from isolation and physical distancing measures. The study determined the durability of SARS-CoV-2 antibodies after an initial infection among Filipinos in Metro Manila, Philippines, and the extent of protection SARS-CoV-2 antibodies confer against reinfection. Methods: We conducted a cohort study to monitor the antibody levels of patients diagnosed with COVID-19. Receptor-binding domain (RBD)-specific antibodies were measured at Days 21, 90, 180, 270 and 360. Antibody levels were reported as geometric mean titers (GMT) with geometric standard deviation (GSD). Differences in GMT were tested using Friedman test and Kruskal Wallis test, with Bonferroni multiple comparisons procedure. Adjusted hazard ratios on the development of probable reinfection were estimated using Cox proportional models. Results: There were 307 study participants included in the study, with 13 dropouts. Study participants received SARS-CoV-2 vaccines at varying times, with 278 participants (90.5%) fully vaccinated by the end of study. The GMT of the study cohort increased over time, from 19.7 U/mL (GSD 11) at Day 21; to 284.5 U/mL (GSD 9.6) at Day 90; 1,061 U/mL (GSD 5.3) at Day 180; 2,003 U/mL (GSD 6.7) at Day 270; and 8,403 U/mL (GSD 3.1) at Day 360. The increase was statistically significant from Day 21 to Day 90 (p<0.0001), Day 90 to Day 180 (p=0.0005), and Day 270 to Day 360 (p<0.0001). Participants with more severe initial infection demonstrated significantly higher antibody levels compared to those with milder infection at Day 21. Sixty-four patients had probable COVID-19 reinfection (incidence of 20.8%, 95% CI 16.4, 25.8%). The GMT of these 64 patients was 411.8 U/mL (GSD 6.9) prior to the occurrence of the probable reinfection. Majority (87.5%) were fully vaccinated. Antibody titers significantly affected the risk of developing reinfection, with adjusted hazard ratio of 0.994, 95% CI 0.992-0.996, p<0.001. Conclusion: Antibody levels against SARS-CoV-2 increased over a one-year follow-up. Higher antibody levels were observed among those with more severe initial infection and those vaccinated. Higher antibody levels are associated with a lower risk of probable reinfection.

High TB burden and low notification rates in the Philippines: The 2016 national TB prevalence survey.

SETTING: The 3rd national tuberculosis (TB) survey in the Philippines in 2007 reported a significant decline in the prevalence of TB. Since then, more significant investments for TB control have been made, yet TB burden estimates from routine surveillance data remain relatively stable. OBJECTIVE: To estimate the prevalence of bacteriologically confirmed pulmonary TB in the Philippines amongst individuals aged ≥15 years in 2016. DESIGN: In March-December 2016, we conducted a population-based survey with stratified, multi-stage cluster sampling of residents in 106 clusters aged ≥15 years. Survey participants were screened for TB by symptom-based interview and digital chest X-ray. Those with cough ≥2 weeks and/or haemoptysis and/or chest X-ray suggestive of TB were requested to submit 2 sputum specimens for Xpert MTB/RIF, direct sputum smear microscopy using LED fluorescent microscopy, and mycobacterial solid culture (Ogawa method). Bacteriologically confirmed pulmonary TB was defined as MTB culture positive and/or Xpert positive. RESULTS: There were 46,689 individuals interviewed, and 41,444 (88.8%) consented to a chest X-ray. There were 18,597 (39.8%) eligible for sputum examination and 16,242 (87.3%) submitted at least one specimen. Out of 16,058 sputum-eligible participants, 183 (1.1%) were smear-positive. There were 466 bacteriologically confirmed TB cases: 238 (51.1%) Xpert positive, 69 (14.8%) culture positive, and 159 (34.1%) positive by both Xpert and culture. The estimated TB prevalence per 100,000 population aged ≥15 years was 434 (95% CI: 350-518) for smear-positive TB, and 1,159 (95% CI: 1,016-1,301) for bacteriologically confirmed TB. CONCLUSION: This nationally representative survey found that the TB burden in the Philippines in 2016 was higher than estimated from routine TB surveillance data. There was no evidence of a decline in smear and culture positive TB from the 2007 survey despite significant investments in TB control. New strategies for case-finding and patient-centered care must be intensified and expanded.

Early experience with COVID-19 patients in a private tertiary hospital in the Philippines: Implications on surge capacity, healthcare systems response, and clinical care.

BACKGROUND: Our healthcare institution was one of the first to see SARS CoV-2 cases in the country. We describe the early COVID-19 experience of a private hospital in the Philippines and discuss the healthcare system response in the setting of surge capacity. METHODS: We reviewed the medical records of adult COVID-19 hospitalized patients admitted in March 2020. We reported their demographic and clinical characteristics using descriptive statistics. RESULTS: Of 40 patients admitted, 23 (57.5%) were male and 19 (47.5%) were aged <60 years. Most (n = 27, 67.5%) had moderate-risk, 9 (22.5%) had high-risk, and 4 (10%) had low-risk COVID-19. SARS-CoV-2 testing took 5.5 (range 1-10) days. Overall mortality rate was 6/40 (15.0%). Clinical cure was documented in all low-risk patients, 25 (92.6%) moderate-risk patients, and only 1 (11.1%) high-risk patient. In response to the surge, the hospital rapidly introduced one-way traffic systems, dedicated screening, triage and Emergency Department areas for COVID-19, a clinical pathway, engineering controls, patient cohorting, and strict infection prevention and control measures. CONCLUSION: Majority of patients recovered from COVID-19. Older age and high-risk pneumonia were associated with poor outcomes. Adaptations to hospital structure and staff were quickly made in response to surge capacity, although our response was hampered by prolonged time to COVID-19 confirmation. Our study underscores the urgent need for rapid adaptive response by the healthcare system to address the surge of cases.

Controversy and debate on dengue vaccine series-paper 1: review of a licensed dengue vaccine: inappropriate subgroup analyses and selective reporting may cause harm in mass vaccination programs.

Severe life-threatening dengue fever usually occurs when a child is infected by dengue virus a second time. This is caused by a phenomenon called antibody-dependent enhancement (ADE). Since dengue vaccines can mimic a first infection in seronegative children (those with no previous infection), a natural infection later in life could lead to severe disease. The possibility that dengue vaccines can cause severe dengue through ADE has led to serious concern regarding the safety of mass vaccination programs. A published meta-analysis addressed this safety issue for a new vaccine against dengue fever-Dengvaxia. The trials in this meta-analysis have been used to campaign for mass vaccination programs in developing countries. We discuss the results of this paper and point out problems in the analyses. Reporting the findings in an Asian trial (CYD14), the authors show a sevenfold rise in one outcome-hospitalization for dengue fever in children <5 years old. However, they fail to point out two signals of harm for another outcome-hospitalization for severe dengue fever (as confirmed by an independent data monitoring committee): 1. In children younger than 9 years, the relative risk was 8.5 (95% confidence interval [CI]: 0.5, 146.8), and 2. In the overall study group, the relative risk was 5.5 (95% CI: 0.9, 33). The authors conduct a subgroup analysis to support claims that the vaccine is probably safe among children aged 9 years or more. This subgroup analysis has limited credibility because: (1) it was a post hoc analysis; (2) it was one of a large number of subgroup analyses; (3) the test of interaction was not reported, but was insignificant (P = 0.14); and (4) there is no biological basis for a threshold age of 9 years. The more likely explanation for the higher risk in younger children is ADE, that is, more frequent seronegativity, rather than age itself. The selective reporting and inappropriate subgroup claims mask the potential harm of dengue mass vaccination programs. Countries planning public use of the vaccine must conduct diligent postmarketing surveillance, secure informed consent from parents of potential recipients, and closely monitor the results of ongoing long-term follow-up of clinical trial participants.

Reminder systems to improve patient adherence to tuberculosis clinic appointments for diagnosis and treatment.

BACKGROUND: People with active tuberculosis (TB) require six months of treatment. Some people find it difficult to complete treatment, and there are several approaches to help ensure completion. One such system relies on reminders, where the health system prompts patients to attend for appointments on time, or re-engages people who have missed or defaulted on a scheduled appointment. OBJECTIVES: To assess the effects of reminder systems on improving attendance at TB diagnosis, prophylaxis, and treatment clinic appointments, and their effects on TB treatment outcomes. SEARCH METHODS: We searched the Cochrane Infectious Diseases Group Specialized Register, Cochrane Effective Practice and Organization of Care Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS, CINAHL, SCI-EXPANDED, SSCI, mRCT, and the Indian Journal of Tuberculosis without language restriction up to 29 August 2014. We also checked reference lists and contacted researchers working in the field. SELECTION CRITERIA: Randomized controlled trials (RCTs), including cluster RCTs and quasi-RCTs, and controlled before-and-after studies comparing reminder systems with no reminders or an alternative reminder system for people with scheduled appointments for TB diagnosis, prophylaxis, or treatment. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data and assessed the risk of bias in the included trials. We compared the effects of interventions by using risk ratios (RR) and presented RRs with 95% confidence intervals (CIs). Also we assessed the quality of evidence using the GRADE approach. MAIN RESULTS: Nine trials, including 4654 participants, met our inclusion criteria. Five trials evaluated appointment reminders for people on treatment for active TB, two for people on prophylaxis for latent TB, and four for people undergoing TB screening using skin tests. We classified the interventions into 'pre-appointment' reminders (telephone calls or letters prior to a scheduled appointment) or 'default' reminders (telephone calls, letters, or home visits to people who had missed an appointment).For people being treated for active TB, clinic attendance and TB treatment completion were higher in people receiving pre-appointment reminder phone-calls (clinic attendance: 66% versus 50%; RR 1.32, 95% CI 1.10 to 1.59, one trial (USA), 615 participants, low quality evidence; TB treatment completion: 100% versus 88%; RR 1.14, 95% CI 1.02 to 1.27, one trial (Thailand), 92 participants, low quality evidence). Clinic attendance and TB treatment completion were also higher with default reminders (letters or home visits) (clinic attendance: 52% versus 10%; RR 5.04, 95% CI 1.61 to 15.78, one trial (India), 52 participants, low quality evidence; treatment completion: RR 1.17, 95% CI 1.11 to 1.24, two trials (Iraq and India), 680 participants, moderate quality evidence).For people on TB prophylaxis, clinic attendance was higher with a policy of pre-appointment phone-calls (63% versus 48%; RR 1.30, 95% CI 1.07 to 1.59, one trial (USA), 536 participants); and attendance at the final clinic was higher with regular three-monthly phone-calls or nurse visits (93% versus 65%, one trial (Spain), 318 participants).For people undergoing screening for TB, three trials of pre-appointment phone-calls found little or no effect on the proportion of people returning to clinic for the result of their skin test (three trials, 1189 participants, low quality evidence), and two trials found little or no effect with take home reminder cards (two trials, 711 participants). All four trials were conducted among healthy volunteers in the USA. AUTHORS' CONCLUSIONS: Policies of sending reminders to people pre-appointment, and contacting people who miss appointments, seem sensible additions to any TB programme, and the limited evidence available suggests they have small but potentially important benefits. Future studies of modern technologies such as short message service (SMS) reminders would be useful, particularly in low-resource settings.

Intravenous immunoglobulin for treating sepsis, severe sepsis and septic shock.

BACKGROUND: Mortality from sepsis and septic shock remains high. Results of trials on intravenous immunoglobulins (IVIG) as adjunctive therapy for sepsis have been conflicting. This is an update of a Cochrane review that was originally published in 1999 and updated in 2002 and 2010. OBJECTIVES: To estimate the effects of IVIG as adjunctive therapy in patients with bacterial sepsis or septic shock on mortality, bacteriological failure rates, and duration of stay in hospital. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 6), MEDLINE (1966 to December 2012), and EMBASE (1988 to December 2012). We contacted investigators in the field for unpublished data. The original search was performed in 1999 and updated in 2002 and 2008. SELECTION CRITERIA: We included randomized controlled trials comparing IVIG (monoclonal or polyclonal) with placebo or no intervention in patients of any age with bacterial sepsis or septic shock. DATA COLLECTION AND ANALYSIS: Two authors independently assessed the studies for inclusion and undertook methodologic quality assessment and data abstraction. We conducted pre-specified subgroup analyses by type of immunoglobulin preparation. MAIN RESULTS: We included 43 studies that met our inclusion criteria in this updated review out of 88 potentially eligible studies. The studies included a large polyclonal IVIG trial in neonates that was concluded in 2011 and classified as ongoing in the 2010 version of this review. Pooled analysis of polyclonal and monoclonal IVIG was not done due to clinical heterogeneity. Subgroup analysis of 10 polyclonal IVIG trials (n = 1430) and seven trials on IgM-enriched polyclonal IVIG (n = 528) showed significant reductions in mortality in adults with sepsis compared to placebo or no intervention (relative risk (RR) 0.81; 95% confidence interval (CI) 0.70 to 0.93 and RR 0.66; 95% CI 0.51 to 0.85, respectively). Subgroup analysis of polyclonal IVIG in neonates, which now includes the recently concluded large polyclonal IVIG trial, showed no significant reduction in mortality for standard IVIG (RR 1.00; 95% CI 0.92 to 1.08; five trials, n = 3667) and IgM-enriched polyclonal IVIG (RR 0.57; 95% CI 0.31 to 1.04; three trials, n = 164). Sensitivity analysis of trials with low risk of bias showed no reduction in mortality with polyclonal IVIG in adults (RR 0.97; 95% CI 0.81 to 1.15; five trials, n = 945) and neonates (RR 1.01; 95% CI 0.93 to 1.09; three trials, n = 3561). Mortality was not reduced among patients (eight trials, n = 4671) who received anti-endotoxin antibodies (RR 0.99; 95% CI 0.91 to1.06) while anti-cytokines (nine trials, n = 7893) demonstrated a marginal reduction in mortality (RR 0.92; 95% CI 0.86 to 0.97). AUTHORS' CONCLUSIONS: Polyclonal IVIG reduced mortality among adults with sepsis but this benefit was not seen in trials with low risk of bias. Among neonates with sepsis, there is sufficient evidence that standard polyclonal IVIG, as adjunctive therapy, does not reduce mortality based on the inclusion of the large polyclonal IVIG trial on neonates. For Ig-M enriched IVIG, the trials on neonates and adults were small and the totality of the evidence is still insufficient to support a robust conclusion of benefit. Adjunctive therapy with monoclonal IVIGs remains experimental.

The accessibility and utilization of mobile phones among TB patients: A feasibility survey for short messaging service (SMS) as a strategy to improve adherence to TB services

OBJECTIVES: To estimate the proportion of TB patients who have access to mobile phones and to describe mobile phone utilization practices of TB patients. METHODS: Six public and six private TB clinics representing the four districts of Metro Manila and one institution in Cavite were purposively selected for this cross-sectional survey conducted in 2006. Using an interviewer-administered questionnaire, patients suspected to have TB, those newly diagnosed and those currently on treatment under either DOTS or non-DOTS were interviewed. RESULTS: Of the 337 patients interviewed, 65% (95% CI 60.2 to 70.6) have access to mobile phones (45% currently own a mobile phone and 20% share a mobile phone with a household member). The mean duration of ownership was 1.8 years (SD1.7). Almost all had prepaid subscriptions (99%) and 72% had some credit/load in their mobile phones at the time of interview. Of the three existing networks, subscription to SMART was highest, followed by the Globe network. Most of them use their phones for social purposes and emergency-related communications. Most of the respondents were male (60%) in the age group of 20-39 (54%) and 40-59 years old (33%). Half of the respondents were from public TB clinics (52%). On multivariable analysis, patients consulting in private clinics [OR 2.25, 95% CI 1.36 to 3.74], belonging to the younger age of CONCLUSION: Considering the fair access (65%) to mobile phones of the patients interviewed, it is feasible to conduct a pilot intervention using SMS as a strategy to improve adherence to treatment. The intervention should consider that majority use prepaid subscriptions and that sharing of phones among household members is a common practice.

Reminder systems and late patient tracers in the diagnosis and management of tuberculosis.

BACKGROUND: Reminder systems and late patient tracers as strategies to improve patients' adherence to tuberculosis screening, diagnosis, and treatment are used in some countries, but their effectiveness has not previously been systematically reviewed. OBJECTIVES: To assess the effects of reminder systems and late patient tracers on completion of diagnostics, commencement of treatment in people referred for curative or prophylactic treatment of tuberculosis, completion of treatment in people starting curative or prophylactic treatment for tuberculosis, and cure in people being treated for active tuberculosis. SEARCH STRATEGY: We searched the Cochrane Infectious Diseases Group Specialized Register (June 2008), Cochrane Effective Practice and Organization of Care Group Specialized Register (April 2007), CENTRAL (The Cochrane Library 2008, Issue 2), MEDLINE (1966 to June 2008), EMBASE (1974 to June 2008), LILACS (1982 to June 2008), CINAHL (1982 to June 2008), SCI-EXPANDED (1945 to June 2008), SSCI (1956 to June 2008), mRCT (June 2008), Indian Journal of Tuberculosis (1983 to June 2008), and reference lists. We also contacted researchers working in the field. SELECTION CRITERIA: Randomized controlled trials (RCTs), including cluster RCTs and quasi-RCTs, and controlled before-and-after studies comparing any reminders or late patient tracers with no or other kinds of reminders or late patient tracers. We included people in any setting who require treatment for tuberculosis or require prophylaxis against tuberculosis and are referred to tuberculosis diagnostic or screening services. DATA COLLECTION AND ANALYSIS: Two authors independently assessed trial risk of bias and extracted data. No meta-analysis could be undertaken due to the heterogeneity of interventions across trials. MAIN RESULTS: Nine trials involving 5257 participants met the inclusion criteria. Three assessed the use of late patient tracers, and six assessed reminder systems. Late patient tracers (home visit and letter) were shown to be beneficial in increasing adherence to tuberculosis treatment compared with no late patient tracer. The results from almost all the reminder trials, except one, show benefits of different types of reminders compared to no reminder on adherence to tuberculosis clinic appointments. AUTHORS' CONCLUSIONS: The included trials show significantly better outcomes among those tuberculosis patients for which late patient tracers and reminders are used. Studies of good quality (large and with rigorous study design) are needed to decide the most effective late patient tracer actions and reminders in different settings. Future studies of reminders in chemoprophylaxis and treatment settings would be useful.