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The ozonesonde observations in Hanoi, Vietnam, over 14 years since 2004, have confirmed an enhancement in lower tropospheric ozone concentration at about 3 km altitude in the spring season. We investigated the evolution of the ozone enhancement from analysis of meteorological data, backward trajectories, and model sensitivity experiments. In spring, air masses over Hanoi exhibit strong height dependence. At 3 km, the high‐ozone air masses originate from the land area to the west of Hanoi, while low‐ozone air masses below about 1.5 km are from the oceanic area to the east. Above 4 km, the air masses are mostly traced back to the farther west area. The chemical transport model simulations revealed that precursor emissions from biomass burning in the inland Indochina Peninsula have the largest contribution to the lower tropospheric ozone enhancement, which is transported upward and eastward and overhangs the clean air intrusion from the ocean to the east of Hanoi. At this height level, the polluted air has the horizontal extent of about 20° in longitude and latitude. The polluted air observed in Hanoi is transported further east and widely spread over the northern Pacific Ocean. Plain Language Summary: Ozone in the lower atmosphere acts as an air pollutant and is one of the strong greenhouse gases. Understanding chemical and transport processes that control ozone variations provide important implications for the origin of air pollution and for climate change. In the past 20 years, the global tropospheric ozone amount has increased in the tropics and subtropics, with particularly large increases in Southeast Asia. We analyze a seasonal enhancement in ozone over Hanoi, Vietnam, using the 14‐year record of upper air ozone measurements that began in 2004. The measurements reveal high levels of ozone particularly during the spring that peak at around 3 km. Numerical model simulations show that agricultural burning in the inland Indochina Peninsula is the major contributor to these high ozone amounts that are transported upward and eastward and overhang the clean air from the ocean to the east of Hanoi. Over time, the high‐ozone air observed in Hanoi is transported further east and widely spread over the northern Pacific Ocean. The identified source of the ozone enhancements and its three‐dimensional distribution provide new insights into the impact of agricultural burning over Southeast Asia on large‐scale ozone distributions and are relevant to global air quality and climate studies. Key Points: Ozonesonde observations in Hanoi, Vietnam, for about 14 years since 2004 display an ozone enhancement at ∼3 km altitude in March–AprilEnhanced ozone air at ∼3 km originates from burning areas west of Hanoi whereas low‐ozone near‐surface air is marine from the eastModel experiments show biomass fires in the Indochina Peninsula are the cause of Hanoi's enhanced ozone [ABSTRACT FROM AUTHOR]

Serum samples from 54 monkeys were collected from healthy individuals in a monkey farm in Luzon island, Philippines, in 1999, and examined by IgM-capture ELISA and indirect IgG ELISA for the presence of dengue (DEN), Japanese encephalitis (JE) and chikungunya (CHIK) viruses. The positive rates for IgM ELISA were 3.7, 35.2 and 14.8% against DEN, JE and CHIK, respectively. Higher positive rates were obtained when indirect IgG ELISA was used: 100% against flaviviruses (JE or DEN) and 59.3% against CHIK virus. The results indicate a high prevalence of flavivirus infections such as JE and DEN, and a lesser prevalence of CHIK virus infections, among monkeys in the Philippines. These findings suggest possible sylvatic transmission cycles of these viruses. [ABSTRACT FROM AUTHOR]

This study was carried out to define the role of cattle as an amplifier of Rift Valley fever. Three areas of different density of cattle population were surveyed. Cattle do not seem to play a significant role as an amplifier of the virus in human beings. Zusammenfassung Eine seroepidemiologische Untersuchung von Rift Valley Fever in Zambia Diese Untersuchung wurde ausgeführt, um die Rolle der Rinder als Träger von RVF festzustellen. Drei Gebiete mit unterschiedlichen Rinderbevölkerungen wurden untersucht. Es scheint, daß Rinder keine bedeutende Rolle bei der Verbreitung des Virus unter Menschen spielen. [ABSTRACT FROM AUTHOR]

A 37-year-old Japanese male was admitted to Nagasaki University Hospital with abrupt onset of biphasic fever, general malaise and myalgia 9 days after coming back to Japan from Manila. He developed a rubella like erythematous rash 3 days after admission and purpuric eruption one week after admission. A biopsied specimen from the purpura revealed lymphocytic vasculitis with T cell dominance and without immunoglobulin or complement deposition around the blood vessels. RT-PCR analysis on peripheral blood mononuclear cells using dengue virus specific primers confirmed the diagnosis of type 3 dengue fever. PCR analysis using virus specific primers is a rapid and valuable method for making a correct diagnosis of dengue fever.