Comparison of End Tidal Carbon Monoxide Levels between Conventional Cigarette, Electronic Cigarette and Heated Tobacco Product among Asiatic Smokers.

BACKGROUND: Electronic nicotine delivery systems (ENDS) and heated tobacco products (HTPs) are noncombustible tobacco products which have been found to generate aerosols containing lower levels of Harmful and Potentially Harmful Constituents (HPHCs) in comparison to conventional cigarettes. Objective: This quasi experimental study measured and compared the end tidal carbon monoxide (eCO) levels of participants after use of ENDS, HTPs and conventional cigarettes. Methods: In total 45 smokers, each smoking at least 10 conventional cigarettes per day for 5 years participated in the study. Based on their preference, participants used only one of the tobacco products (ENDS, HTPs, or conventional cigarette) and were briefed about the product use based on manufacturer's instructions. The eCO levels were obtained at baseline, followed by 5, 10, 15, 30 and 45 min respectively after the product use. Results: There was significant increase in eCO levels for conventional cigarettes as compared to other modes. Peak eCO levels of 20.2 ± 0.86 ppm, 8.8 ± 1.56 ppm and 6.0 ± 1.36 ppm was achieved at 30 min, 15 min and 10 min for conventional cigarettes, ENDS and HTPs respectively. However, the levels were significantly lower in ENDS and HTPs. Conclusion: Even though ENDS and HTPs may have produced significantly lower eCO than conventional cigarettes, the significantly increasing levels over time from baseline which was not shown before is a cause of concern. As of now, their use as an alternate to cigarettes needs to be considered under regulatory framework.

Early warning and response system (EWARS) for dengue outbreaks: Recent advancements towards widespread applications in critical settings.

BACKGROUND: Dengue outbreaks are increasing in frequency over space and time, affecting people's health and burdening resource-constrained health systems. The ability to detect early emerging outbreaks is key to mounting an effective response. The early warning and response system (EWARS) is a toolkit that provides countries with early-warning systems for efficient and cost-effective local responses. EWARS uses outbreak and alarm indicators to derive prediction models that can be used prospectively to predict a forthcoming dengue outbreak at district level. METHODS: We report on the development of the EWARS tool, based on users' recommendations into a convenient, user-friendly and reliable software aided by a user's workbook and its field testing in 30 health districts in Brazil, Malaysia and Mexico. FINDINGS: 34 Health officers from the 30 study districts who had used the original EWARS for 7 to 10 months responded to a questionnaire with mainly open-ended questions. Qualitative content analysis showed that participants were generally satisfied with the tool but preferred open-access vs. commercial software. EWARS users also stated that the geographical unit should be the district, while access to meteorological information should be improved. These recommendations were incorporated into the second-generation EWARS-R, using the free R software, combined with recent surveillance data and resulted in higher sensitivities and positive predictive values of alarm signals compared to the first-generation EWARS. Currently the use of satellite data for meteorological information is being tested and a dashboard is being developed to increase user-friendliness of the tool. The inclusion of other Aedes borne viral diseases is under discussion. CONCLUSION: EWARS is a pragmatic and useful tool for detecting imminent dengue outbreaks to trigger early response activities.

Understanding Giardia infections among rural communities using the one health approach.

The epidemiology of giardiasis in rural villages in Peninsular Malaysia was examined in the context of the One Health triad that encompasses humans, animals and environment (i.e. river water). A cross-sectional study was carried out among five rural communities in Malaysia to determine the prevalence of Giardia duodenalis in humans, animals and river water. Fecal samples collected from humans and animals were examined by light microscopy. Water was sampled from the rivers adjacent to the target communities and investigated for the occurrence of Giardia cysts. The isolated cysts were further genotyped targeting the glutamate dehydrogenase and triosephosphate isomerase genes. The overall prevalence of G. duodenalis was 6.7% (18/269) and 4.7% (8/169) among humans and animals, respectively. Giardia cysts (mean concentration range: 0.10-5.97 cysts/L) were also found in adjacent rivers at four out of the five villages examined. At Kemensah and Kuala Pangsun, Giardia cysts were isolated from humans [rate: 3.7% each (of 54 each)], animals [rates: 6.3% (of 62) and 11.3% (of 16), respectively] and river water [average concentration of 9 samples each: 0.83±0.81 and 5.97±7.00, respectively]. For both villages at Pos Piah and Paya Lebar, 12.2% (of 98) and 6.1% (of 33) of collected human samples were infected, respectively whilst none of the collected animals samples in these villages were found to be positive. The river water samples of these two villages were also contaminated (average concentration: 0.20±0.35 (of 9) and 0.10±0.19 (of 3), respectively). In conclusion, Giardia cysts were simultaneously observed in the human-animal-environment (i.e., river water) interfaces in at least two of five studied communities highlighting a vital need to improve understanding on the interplay of transmission dynamics, the role of infected humans and animals in contaminating the water sources and the role of water as a vehicle of disease transmission in these communities. Indeed, this study illustrates the One Health approach which is to recognize that the optimal health of humans are interconnected with the well-being of animals and their environment.

Detection of helminth infections in dogs and soil contamination in rural and urban areas.

A study was conducted to determine the helminthes in dog's feces and soil samples from urban and rural areas. Six species of nematodes (Toxocara sp, an undetermined nematode larvae, Strongyloides sp larvae, Ascaris sp ova, hookworm ova, Trichuris sp ova) and one species of Cestode (Taenia sp) were found in 175 stool samples. Seventy-eight point nine percent of stool samples were positive for helminthes. Mixed infection with at least one parasite was found in 32.6% of the samples. The prevalence of helminth infection ranged from 1.1% to 45.1%. The prevalence of hookworm sp was the highest with 45.1%. The highest prevalence in urban dogs was hookworm sp in 76.7% and in rural areas was Ascaris sp in 48.7%. Soil samples were also examined to determine contamination of the environment, especially due to Toxocara canis, as a potential source of infection. Urban soil samples showed a higher contamination rate with 26.7% compared to rural areas with 4.9%. Toxocara ova were the most prevalent helminthes contaminating the soil with 12.1%. This study showed that humans from both urban and rural areas are at risk of acquiring helminth infection from contaminated soil.

Parasitic infections among Orang Asli (aborigine) in the Cameron Highlands, Malaysia.

In April 2004, an outbreak of acute diarrheal illness occurred among the Orang Asli (aborigine) in the Cameron Highlands, Pahang State, Peninsular Malaysia, where rotavirus was later implicated as the cause. In the course of the epidemic investigation, stool samples were collected and examined for infectious agents including parasites. Soil transmitted helminthes (STH), namely Ascaris lumbricoides (25.7%), Trichuris trichiura (31.1%) and hookworm (8.1%), and intestinal protozoa, which included Giardia lamblia (17.6%), Entamoeba histolytica/E. dispar (9.4%), Blastocystis hominis (8.1%) and Cryptosporidium parvum (2.7%), were detected. Forty-four (59.5%) were infected with at least one parasite, 24 (32.4%), 12 (16.2%) and 8 (10.8%) had single, double and triple parasitic infections, respectively. STH were prevalent with infections occurring as early as in infancy. Giardia lamblia, though the most commonly found parasite in samples from symptomatic subjects, was within the normally reported rate of giardiasis among the various communities in Malaysia, and was an unlikely cause of the outbreak. However, heavy pre-existing parasitic infections could have contributed to the severity of the rotavirus diarrheal outbreak.

Seroprevalence of cysticercosis in a rural village of Ranau, Sabah, Malaysia.

The objective of this study was to determine exposure to cysticercosis among a rural population in a selected village in Ranau, Sabah, Malaysia. A total of 135 serum samples were analyzed. The result showed that the seroprevalence of cysticercosis antibodies was 2.2%. There was no significant difference in the seroprevalence among age groups (p=0.307). Even though there was a slightly higher antibody titer in males compared to females, the difference was not significant (p=0.400). The results indicate evidence of exposure to cysticercosis in this rural population.

Epidemiology of malaria in Attapeu Province, Lao PDR in relation to entomological parameters.

Surveys were conducted in malaria-endemic villages in the southern province of Attapeu, Lao PDR during various seasons over a 3-year period. All-night mosquito landing collections, blood surveys and a case-control study were conducted. Plasmodium falciparum was the predominant species, and slide positivity rates were higher during the transition/dry season compared with the wet season. Anopheles dirus A was found to be the primary vector, and sporozoite rates were highest during the transition/dry season. Anopheles dirus was found to be endophagic and endophilic. Not using insecticide-treated bed nets, houses close to breeding sites and sleeping away from home were risk factors associated with malaria.

Malaria transmission by Anopheles dirus in Attapeu Province, Lao PDR.

A study was carried out in four malaria-endemic villages in Attapeu Province, in the southern region of Lao PDR. All-night human landing collections were carried out in May, August, and October 2002, to determine malaria vectors. At the same time, mass blood surveys were also carried out in the same villages. Anopheles dirus was the predominant species in three of the study villages. Sporozoites were found only in An. drius from Phou Hom. However, in Beng Phoukham, An. dirus was positive for oocysts. The distribution of malaria cases was highest in Phou Hom and this correlated well with the vectorial capacity of An. dirus. The risk for infection from An. dirus was also high, at 0.99.

Endemic malaria in four villages in Attapeu Province, Lao PDR.

A study was conducted in four villages in Attapeu Province, Lao PDR in 2002 to determine malaria endemicity. The study villages were Mixay, Beng Phoukham, Phou Vong and Pier Geo. Mass blood surveys were conducted in May, August, and October. Finger prick blood was collected for thick and thin blood film as well as for dipstick. The slide positivity rate was highest in Phou Hom in October (41.7%). Plasmodium falciparum was the dominant species comprising more than 80% of the cases. As a whole, the distribution of malaria was similar among males and females. Children below 15 years accounted for a large percentage of the cases. The sensitivity of the optimal dipstick was 62.36 and the specificity was 61.7. Microscopy was taken as the gold standard. Anopheles dirus was found to be the main vector and the vectorial capacity correlated well with the cases.