Alexander Augusto Martinez Caballero

• PhD in Biotechonology, Medical Technologist
• Head of Department at Gorgas Memorial Institute for Health Studies

The COVID-19 pandemic highlighted the critical role of viral genomic surveillance, prompting numerous countries to enhance their monitoring systems for acute respiratory infections (ARIs), especially influenza-like illnesses (ILIs). Given the significance of asymptomatic cases in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmis...

The Enterobacter cloacae complex, a prominent bacterium responsible worldwide for most bloodstream infections in the hospital environment, has shown broad-spectrum antibiotic resistance, including carbapenems. Therefore, bacteriophages have again attracted the attention of the science and medical community as an alternative to control Multidrug res...

Chlamydia trachomatis (CT) is a bacterium that causes one of the most common sexually transmitted infections (STIs) worldwide. In Panama, the prevalence of genital Chlamydia trachomatis (CT) among adolescents is 15.8%. However, no data describing circulating CT genotypes or evaluating molecular resistance are available. This study aims to determine...

Panama is a country with endemic Dengue virus (DENV) transmission since its reintroduction in 1993. The four serotypes have circulated in the country and the region of the Americas, however, DENV-4 confirmed autochthonous cases have not been identified since 2000, despite its circulation in neighboring countries. Here, we report DENV-4 detection in...

Latin America and Caribbean (LAC) regions were an important epicenter of the COVID-19 pandemic and SARS-CoV-2 evolution. Through the COVID-19 Genomic Surveillance Regional Network (COVIGEN), LAC countries produced an important number of genomic sequencing data that made possible an enhanced SARS-CoV-2 genomic surveillance capacity in the Americas,...

Low-frequency mutations associated with drug resistance have been related to virologic failure in subjects with no history of pre-treatment and recent HIV diagnosis. In total, 78 antiretroviral treatment (ART)-naïve subjects with a recent HIV diagnosis were selected and followed by CD4+ T lymphocytes and viral load tests to detect virologic failure...

Here, we present the complete genome sequence of Enterobacter phage vB_EcRAM-01, isolated from waters of the Río Abajo river, in Panama City, Panama. This phage has deployed lytic activity against the Enterobacter cloacae complex, a pathogen of clinical importance in intensive care units. It belongs to the Myoviridae family and has a double-strande...

The timely release of SARS-CoV-2 first genomic sequences allowed the identification of the etiologic agent and development of diagnostic protocols. Genomic sequencing was a crucial step in generating data for driving laboratory response and detections of SARS-CoV-2 since the start of the COVID-19 pandemic. Because of all the progression and achieve...

Bacteriófagos (fagos) son los virus que infectan bacterias. Los fagos en algunas regiones del mundo (por ejemplo, el Fagolac® en Chile, SalmoFree® en Colombia) suelen ser usados en la industria alimentaria para el control de patógenos y también, han sido propuestos para el tratamiento de enfermedades bacterianas (PYO Bacteriophage, Tbilisi, Georgia...

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a major international public health concern. The World Health Organization (WHO) declared the pandemic of coronavirus disease 2019 (COVID-19) on March 11, 2020. In Panama, the first SARS-CoV-2 infection was confirmed on March 9, 2020, and the first fatal case a...

Se presentan aquí los hallazgos genómicos y proteómicos de vB_EcRAM-01 un novel fago que infecta el Complejo E. cloacae en Panamá.

We report a case of reinfection by SARS-CoV-2 with the second virus harboring amino acid changes in the Spike protein (141-143del, D215A, ins215AGY, L452R, D614 G), orf1a, helicase, orf3a, and Nucleocapside. The virus associated with the reinfection, from an endemic lineage containing the S:L452R immune escape mutation, was circulating in Panama at...

Brazil experienced a large dengue virus (DENV) epidemic in 2019, highlighting a continuous struggle with effective control and public health preparedness. Using Oxford Nanopore sequencing, we led field and classroom initiatives for the monitoring of DENV in Brazil, generating 227 novel genome sequences of DENV1-2 from 85 municipalities (2015–2019)....

This paper presents new data about Rickettsia species detected in ticks collected from wild animals, using 16S rRNA, gltA and ompA. Rickettsia DNA was found in 66 of 101 ticks. Using EZ BioCloud libraries were produced reads that identified Rickettsia aeschlimannii, and Illumina BaseSpace produced reads of Rickettsia rickettsii group, Rickettsia be...

There is limited evidence regarding severe acute respiratory syndrome coronavirus 2 infection in the placenta of pregnant women who tested positive, and if this could be a route for vertical transmission of the virus in utero. We present the cases of 2 pregnant women in their third trimester who were admitted for delivery by cesarean delivery and w...

We report an epidemiologic analysis of 4,210 cases of infection with severe acute respiratory syndrome coronavirus 2 and genetic analysis of 313 new near-complete virus genomes in Panama during March 9–April 16, 2020. Although containment measures reduced R0 and Rt, they did not interrupt virus spread in the country.

Objectives To determine the prevalence and risk factors of genital Chlamydia trachomatis (CT) among school-going sexually experienced male and female adolescents in Panama. Methods We conducted two multisite cross-sectional studies using two-stage cluster sampling to select adolescents aged 14–19 years attending urban public high schools (URB) in...

Background With more than 50000 accumulated cases, Panama has one of the highest incidences of SARS-CoV-2 in Central America, despite the fast implementation of disease control strategies. We investigated the early transmission patterns of the virus and the outcomes of mitigation measures in the country. Methods We collected information from epidem...

Most of the information on clinical factors related to HIV infection is focused on key populations and young people. Therefore, there is little information on clinical factors related to HIV infection in older persons (>45 years old). In this study, data on CD4 lymphocyte counts were analyzed on adults who are linked to care and have their first CD...

Background: There is scant information on STI prevalence and risk factors among Latin American indigenous populations. We investigated STI prevalence and risk factors among adolescents of the Comarca Ngäbe-Buglé (CNB) indigenous region of Panama. Methods: A population-based cross-sectional study was conducted among school-going adolescents aged...

Background Few data exist on cervico-vaginal STI among adolescents in Panama. The aim of this study was to determine the prevalence and correlates of cervico-vaginal STIs among female school-going adolescents in urban regions of Panama. Methods A multicentric cross sectional study using multistage cluster sampling, with random selection of schools...

Background Consistent condom use, defined as using a condom in every sexual encounter, is an effective measure for preventing sexually transmitted infections (STIs). However, few studies have examined condom use among Latin American youth. This study estimated the correlates of reported condom use among school-going adolescents in four urban sites...

Background The Comarca Ngäbe-Buglé (CNB), situated in western Panama, is home to over 200,000 indigenous peoples; the region has the highest levels of multidimensional poverty in the country. The prevalence and correlates of syphilis and HIV have not been previouslydescribed among adolescents of CNB. Methods A cross sectional study, using multista...

The clinical and pathologic characterisation of two fatal cases of tick-borne rickettsiosis in rural (El Valle) and urban (City of Panama) Panama are described. Clinical and autopsy findings were non-specific, but the molecular analysis was used to identify Rickettsia rickettsii in both cases. No ticks were collected in El Valle, while in the urban...

Determination of HIV drug resistance (HIVDR) is becoming an integral baseline HIV evaluation for newly infected subjects, as the level of pre-treatment resistance is increasing worldwide. Until now, the gold standard for monitoring ART mutations is the Sanger sequencing method, however, next-generation sequencing technologies (NGS) because high-thr...

Introduction Moral judgments (MJ) against people living with HIV (PLHIV), and belief of HIV transmission through casual contact (CC), lead in varying to degrees to social exclusion, discrimination, and violence. This study estimates the prevalence of HIV and other sexually transmitted infections (STI), and describes manifestations and correlates of...

The Hepatitis B Virus (HBV) is a complex pathogen that is affecting all humanity; however, most of studies aimed at evaluating the diversity and impact of the HBV disease have been performed in regions of Asia and North America. Currently, there is a gap in our knowledge on the variability of HBV in Native American populations. In Panama, the HBV p...

Distribution of symptoms by patients with Zika, dengue, and chikungunya virus infections in the Guna Yala region of Panama, November 27, 2015–January 22, 2016; epidemiologic curve for the outbreak of Zika virus infection in this region; and maximum-likelihood tree of the Zika virus isolated during the outbreak.

The use of antiretroviral therapy in HIV infected subjects prevents AIDS-related illness and delayed occurrence of death. In Panama, rollout of ART started in 1999 and national coverage has reached 62.8% since then. The objective of this study was to determine the level and patterns of acquired drug resistance mutations of clinical relevance (ADR-C...

Univariate and multiple logistic regression analysis for CRM mutation. (DOCX)

The Hepatitis B Virus (HBV) can cause acute or chronic infection it is also associated with the development of liver cancer, thousands of new infections occur on a yearly basis, and many of these cases are located in certain areas of the Caribbean and Latin America. In these areas, the HBV prevalence is still high which makes this virus a serious p...

Hepatitis B Virus (HBV) is an infectious agent that causes more than half of the cases of liver disease and cancer in the world. Globally there are around 250 million people chronically infected with this virus. Despite 16% of the cases of liver disease in Central America are caused by HBV, the information regarding its genetic diversity, genotypes...

The Human immunodeficiency virus type-1 (HIV-1) subtype B is the most predominant clade in Central America; but information about the evolutionary history of this virus in this geographic region is scarce. In this study, we reconstructed the spatiotemporal and population dynamics of the HIV-1 subtype B epidemic in Panama. A total of 761 HIV-1 subty...

Phylogenetic studies have suggested that the HIV-1 epidemic in the Americas is mainly dominated by HIV subtype B. However, countries of South America and the Caribbean have recently reported changes in their circulating HIV-1 genetic profiles. The aim of this study was to characterize the molecular profile of the HIV-1 epidemic in Panama by the ana...

Despite the effectiveness of current hepatitis B virus (HBV) vaccines, it is estimated that 350 million individuals suffer from chronic HBV infection and more than 50% of these affected individuals live on the Asian continent. Panama is a country with a great diversity of foreign groups; the Chinese community is a large example of this phenomenon....

Despite the effectiveness of current hepatitis B virus (HBV) vaccines, it is estimated that 350 million individuals suffer from chronic HBV infection and more than 50% of these affected individuals live on the Asian continent. Panama is a country with a great diversity of foreign groups; the Chinese community is a large example of this phenomenon....

Introduction: Aseptic meningitis outbreaks are commonly caused by viral pathogens with enterovirus a common etiological agent. Between May and June of 2008, an outbreak of 173 cases of aseptic meningitis occurred in the Chiriqui Province of Panama. Molecular techniques were used to identify the etiological agent. Methodology: Cerebrospinal fluid...

To investigate the prevalence of transmitted drug-resistant HIV among adults in Panama by using a modified World Health Organization Threshold Survey (WHO-TS) and to investigate rates of initial resistance among HIV-positive infants in Panama. At the Gorgas Memorial Institute, 47 HIV-positive adults were genotyped for mutations associated with tran...

Rocky Mountain spotted fever (RMSF) is a tick-borne infection caused by Rickettsia rickettsii. We report a cluster of fatal cases of RMSF in 2007 in Panama, involving a pregnant woman and two children from the same family. The woman presented with a fever followed by respiratory distress, maculopapular rash, and an eschar at the site from which a t...

In April 2009, a novel influenza A (H1N1) virus was identified in patients from Mexico and the United States. From 8 May through 25 June 2009, in the Republic of Panama, 467 cases infected with the same virus were identified, 13 of which were hospitalized at the Santo Tomas Hospital in Panama City. Up to the date of this report, no deaths have been...