Freddy Perez

Dr. Freddy Perez

World Health Organization
orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 April 2006 in JAIDS Journal of Acquired Immune Deficiency Syndromes
Verified
Journal Article
Closed access
FPFreddy Perez
Freddy Perez
CZCharity Zvandaziva
Charity Zvandaziva
BEBarbara Engelsmann
Barbara Engelsmann
FDFrançois Dabis
François Dabis
Low uptake of prevention of mother-to-child transmission of HIV (PMTCT) services in resource-limited settings requires new approaches to prevent missed opportunities. Routine HIV testing ("opt-out" testing) in antenatal care (ANC) should be considered. An exploratory cross-sectional survey was conducted in 6 PMTCT sites in rural Zimbabwe. Women who had attended ANC in health centers where PMTCT was provided were surveyed in postnatal services. Of 520 women sampled, 285 (55%) had been HIV tested during their last pregnancy. Primary education or no education (P = 0.02), reporting receiving neither group education in the ANC clinic (P < 0.001) nor individual pretest counseling (P < 0.001), and having attended <6 ANC visits (P < 0.03) were associated with not having been HIV tested. Among the 235 women not HIV tested in ANC, 79% would accept HIV testing if opt-out testing was introduced. Factors associated with accepting the opt-out approach were being <20 years old (P = 0.005), having secondary education or more (P = 0.03), living with a partner (P = 0.001), and the existence of a PMTCT service where the untested women delivered. Thirty-seven women of 235 (16%) would decline routine HIV testing, mainly because of their fear of knowing their HIV status and the need to have their partner's consent. Among the women already tested in ANC (n = 285), 97% would accept the opt-out approach. In Zimbabwe, where 25% of pregnant women are HIV infected, introducing the opt-out strategy for HIV testing may have a far-reaching public health impact on PMTCT. Issues regarding, stigma, quality of post-testing counseling and staffing must be considered, however.

9 January 2019 in Tropical Medicine & International Health
Verified
Journal Article
Open access
PDF file
FPFreddy Perez
Freddy Perez
ALAnthony Llau
Anthony Llau
GGGamaliel Gutierrez
Gamaliel Gutierrez
HBHaroldo Bezerra
Haroldo Bezerra
GCGiovanini Coelho
Giovanini Coelho
JMJose Luis San Martin
Jose Luis San Martin
Objective: Since the 1980s, dengue incidence has increased 30‐fold. However, in 2017, there was a noticeable reduction in reported dengue incidence cases within the Americas, including severe and fatal cases. Understanding the mechanism underlying dengue's incidence and decline in the Americas is vital for public health planning. We aimed to provide plausible explanations for the decline in 2017.Methods: An expert panel of representatives from scientific and academic institutions, Ministry of Health officials from Latin America and PAHO/WHO staff met in October 2017 to propose hypotheses. The meeting employed six moderated plenary discussions in which participants reviewed epidemiological evidence, suggested explanatory hypotheses, offered their expert opinions on each and developed a consensus.Results: The expert group established that in 2017, there was a generalised decreased incidence, severity and number of deaths due to dengue in the Americas, accompanied by a reduction in reported cases of both Zika and chikungunya virus infections, with no change in distribution among age groups affected. This decline was determined to be unlikely due to changes in epidemiological surveillance systems, as similar designs of surveillance systems exist across the region. Although sudden surveillance disruption is possible at a country or regional level, it is unlikely to occur in all countries simultaneously. Retrospective modelling with epidemiological, immunological and entomological information is needed. Host or immunological factors may have influenced the decline in dengue cases at the population level through immunity; however, herd protection requires additional evidence. Uncertainty remains regarding the effect on the outcome of sequential infections of different dengue virus (DENV) types and Zika virus (ZIKV), and vice versa. Future studies were recommended that examine the epidemiological effect of prior DENV infection on Zika incidence and severity, the epidemiological effect of prior Zika virus infection on dengue incidence and severity, immune correlates based on new‐generation ELISA assays, and impact of prior DENV/other arbovirus infection on ZIKV immune response in relation to number of infections and the duration of antibodies in relation to interval of protection. Follow‐up studies should also investigate whether increased vector control intensification activities contributed to the decline in transmission of one or more of these arboviruses. Additionally, proposed studies should focus on the potential role of vector competence when simultaneously exposed to various arboviruses, and on entomological surveillance and its impact on circulating vector species, with a goal of applying specific measures that mitigate seasonal occurrence or outbreaks.Conclusions: Multifactorial events may have accounted for the decline in dengue seen in 2017. Differing elements might explain the reduction in dengue including elements of immunity, increased vector control, and even vector and\or viruses changes or adaptations. Most of the results of this expert consensus group meeting are hypothetical and based on limited evidence. Further studies are needed.

10 November 2009 in BMC International Health and Human Rights
Verified
Journal Article
Open access
PDF file
FPFreddy Perez
Freddy Perez
HBHamady Ba
Hamady Ba
SDSayed G Dastagire
Sayed G Dastagire
MAMathias Altmann
Mathias Altmann
Mortality of children under the age of five remains one of the most important public health challenges in developing countries. In rural settings, the promotion of household and community health practices through community health workers (CHWs) is among the key strategies to improve child health. The objective of this study was to assess the performance of CHWs in the promotion of basic child heath services in rural Mali. A community-based cross-sectional survey was undertaken using multi-stage cluster sampling of wards and villages. Data was collected through questionnaires among 401 child-caregivers and registers of 72 CHWs. Of 401 households suppose to receive a visit by a CHW, 219 (54.6%; confidence interval 95%; 49.6-59.5) had received at least one visit in the last three months before the survey. The mother is the most important caregiver (97%); high percentage being illiterate. Caregivers treat fever and diarrhoea with the correct regimen in 40% and 11% of cases respectively. Comparative analysis between households with and without CHW visits showed a positive influence of CHWs on family health practices: knowledge on the management of child fever (p = < 0.001), non-utilization of antibiotics in home treatment of diarrhoea (p = 0.003), presence of cloroquine in the household (p = 0.002), presence (p = 0.001) and use (p = < 0.001) of bed nets. A total of 27 (38%) CHWs had not received supervision at all, against 45 (63%) who have been followed regularly each month during the last six months. Continuous training, transport means, adequate supervision and motivation of CHWs through the introduction of financial incentives and remuneration are among key factors to improve the work of CHWs in rural communities. Poor performance of basic household health practices can be related to irregular supply of drugs and the need of appropriate follow-up by CHWs.

11 November 2004 in BMJ
Verified
Journal Article
Closed access
PDF file
FPFreddy Perez
Freddy Perez
JOJoanna Orne-Gliemann
Joanna Orne-Gliemann
TMTarisai Mukotekwa
Tarisai Mukotekwa
AMAnna Miller
Anna Miller
MGMonica Glenshaw
Monica Glenshaw
FDFrançois Dabis
François Dabis
Problem Zimbabwe has one of the highest rates of HIV seroprevalence in the world. In 2001 only 4% of women and children in need of services for prevention of mother to child transmission of HIV were receiving them. Design Pilot implementation of the first programme for prevention of mother to child transmission of HIV in rural Zimbabwe. Setting 120 bed district hospital in Buhera district (285 000 inhabitants), Manicaland, Zimbabwe. Key measures for improvement Programme uptake indicators monitored for 18 months; impact of policy evaluated by assessing up-scaling of programme. Strategies for change Voluntary counselling and testing services for HIV were provided in the hospital antenatal clinic. Women identified as HIV positive and informed of their serostatus and their newborn were offered a single dose antiretroviral treatment of nevirapine; mother-child pairs were followed up through routine health services. Nursing staff and social workers were trained, and community mobilisation was conducted. Effects of change No services for prevention of mother to child transmission of HIV were available at baseline. Within 18 months, 2298 pregnant women had received pretest counselling, and the acceptance of HIV testing reached 93.0%. Of all 2137 women who had an HIV test, 1588 (74.3%) returned to collect their result; 326 of the 437 HIV positive women diagnosed had post-test counselling, and 104 (24%) mother-child pairs received nevirapine prophylaxis. Lessons learnt Minimum staffing, an enhanced training programme, and involvement of district health authorities are needed for the implementation and successful integration of services for prevention of mother to child transmission of HIV. Voluntary counselling and testing services are important entry points for HIV prevention and care and for referral to community networks and medical HIV care services. A district approach is critical to extend programmes for prevention of mother to child transmission of HIV in rural settings. The lessons learnt from this pilot programme have contributed to the design of the national expansion strategy for prevention of mother to child transmission of HIV in Zimbabwe.

1 July 2004 in Tropical Medicine & International Health
Verified
Journal Article
Open access
PDF file
FPFreddy Perez
Freddy Perez
TMTarisai Mukotekwa
Tarisai Mukotekwa
AMAnna Miller
Anna Miller
JOJoanna Orne‐Gliemann
Joanna Orne‐Gliemann
MGMonica Glenshaw
Monica Glenshaw
FDFrançois Dabis
François Dabis
Summary: Objective  To report on activities and lessons learned during the first 18 months of a rural programme of prevention of mother‐to‐child transmission of HIV (PMTCT) in Zimbabwe.Methods  The PMTCT services were introduced in Murambinda Mission Hospital (120 beds), Buhera, in 2001. Programme strategies consisted in recruiting counselling staff, training health professionals, improving mother–child health (MCH) facilities and conducting information, education and communication activities within the community to address HIV/AIDS awareness and stigma. The following components were implemented within MCH services: voluntary counselling and testing of HIV using rapid testing, nevirapine short regimen proposed to all HIV‐infected mothers identified and their newborns, support to exclusive breastfeeding for 6‐ and 18‐month mother–child follow‐up. Routine monitoring data collected from August 2001 to February 2003 were used to estimate programme uptake.Results  Of 2471 pregnant women using antenatal services, 2298 were pre‐test counselled, the acceptance of HIV testing reached 92.9%. Of the women who decided to take an HIV test, 1588 (74.3%) returned to collect their result. Overall HIV prevalence was 20.4% (n = 437); 326 of the HIV‐positive women were counselled and 104 (24%) received complete mother–child antiretroviral prophylaxis.Conclusions  Acceptability of HIV testing after counselling has remained above 90% since the onset of the programme. Collection of test results and mother–child follow‐up are among the most challenging activities of the programme. A district approach and community participation are critical to develop PMTCT programmes in rural settings, even with reasonably good MCH services.

10 January 2012 in PLOS Medicine
Verified
Journal Article
Open access
PDF file
ACAndrea L. Ciaranello
Andrea L. Ciaranello
FPFreddy Perez
Freddy Perez
JKJo Keatinge
Jo Keatinge
JPJi-Eun Park
Ji-Eun Park
BEBarbara Engelsmann
Barbara Engelsmann
KFKenneth A. Freedberg
Kenneth A. Freedberg
The World Health Organization (WHO) has called for the “virtual elimination” of pediatric HIV: a mother-to-child HIV transmission (MTCT) risk of less than 5%. We investigated uptake of prevention of MTCT (PMTCT) services, infant feeding recommendations, and specific drug regimens necessary to achieve this goal in Zimbabwe. We used a computer model to simulate a cohort of HIV-infected, pregnant/breastfeeding women (mean age, 24 y; mean CD4, 451/µl; breastfeeding duration, 12 mo). Three PMTCT regimens were evaluated: (1) single-dose nevirapine (sdNVP), (2) WHO 2010 guidelines' “Option A” (zidovudine in pregnancy, infant nevirapine throughout breastfeeding for women without advanced disease, lifelong combination antiretroviral therapy for women with advanced disease), and (3) WHO “Option B” (pregnancy/breastfeeding-limited combination antiretroviral drug regimens without advanced disease; lifelong antiretroviral therapy with advanced disease). We examined four levels of PMTCT uptake (proportion of pregnant women accessing and adhering to PMTCT services): reported rates in 2008 and 2009 (36% and 56%, respectively) and target goals in 2008 and 2009 (80% and 95%, respectively). The primary model outcome was MTCT risk at weaning. The 2008 sdNVP-based National PMTCT Program led to a projected 12-mo MTCT risk of 20.3%. Improved uptake in 2009 reduced projected risk to 18.0%. If sdNVP were replaced by more effective regimens, with 2009 (56%) uptake, estimated MTCT risk would be 14.4% (Option A) or 13.4% (Option B). Even with 95% uptake of Option A or B, projected transmission risks (6.1%–7.7%) would exceed the WHO goal of less than 5%. Only if the lowest published transmission risks were used for each drug regimen, or breastfeeding duration were shortened, would MTCT risks at 95% uptake fall below 5%. Implementation of the WHO PMTCT guidelines must be accompanied by efforts to improve access to PMTCT services, retain women in care, and support medication adherence throughout pregnancy and breastfeeding, to approach the “virtual elimination” of pediatric HIV in Zimbabwe. Please see later in the article for the Editors' Summary