Vaccine derived human-bovine double reassortant rotavirus in infants with acute gastroenteritis

Rotavirukset ovat maailmanlaajuisesti yleisin pienten lasten vakavien ripulitautien aiheuttaja. Ennen rotavirusrokotuksia lasten rotavirusinfektiot aiheuttivat vuosittain kymmeniätuhansia sairaala- ja poliklinikkakäyntejä pienillä lapsilla. RotaTeq® rokote lisättiin Suomen kansalliseen rokotusohjelmaan syyskuussa 2009, kun se oli massiivisten tutkimusten jälkeen todettu turvalliseksi ja tehokkaaksi rokotteeksi rotavirus tautia vastaan. RotaTeq® on elävä, heikennetty rokote, joka sisältää viittä ihmisen ja naudan yhdistelmävirusta. Yhdistelmäviruksissa toinen ulommista pintaproteiineista, VP7 tai VP4, on ihmisperäinen ja toinen nautaperäinen. Suomessa immunisointi tapahtuu 2, 3 ja 5 kuukauden ikäisenä. Tutkimuksen tarkoituksena oli selvittää Tampereen yliopistollisessa sairaalassa (TAYS) syyskuun 2009 ja elokuun 2011 välillä hoidettujen oksennus- ja/tai ripulitautia sairastavien lasten pääasiallisia taudinaiheuttajia. Tutkimukseen osallistuneilta lapsilta kerättiin ulostenäyte, josta tutkittiin rotaviruksen lisäksi norovirus, adenovirus, coronavirus sekä bocavirus PCR- menetelmillä. Rotavirus positiivisista näytteistä selvitettiin lisäksi viruksen uloimman kerroksen kahden pintaproteiinin, VP7 ja VP4 genomi viruksen tyypitystä varten, sekä keskikerroksen proteiinin VP6 sekvenssi mahdollisen rokoteviruksen tunnistamiseksi. Tutkimuksessa löydettiin 3 lasta, joilla oksennus-ja/tai ripulitaudin aiheuttaja oli rokotteesta peräisin oleva uusi yhdistelmävirus. Uudessa rokoteperäisessä viruksessa kaksi RotaTeq® rokotteen virusta ovat yhdistyneet siten, että muodostuneen uuden yhdistelmäviruksen uloimman kerroksen kumpikin proteiini, VP7 ja VP4, ovat ihmisperäisiä. Merkittävänä tutkimustuloksena selvisi, että uusi rokoteperäinen yhdistelmävirus on infektiivinen ja stabiili. Se voi aiheuttaa oksennus-ja/tai ripulitaudin oireita rokotetuilla lapsilla, jotka voivat erittää virusta edelleen ympäristöönsä

Climate Driven Egg and Hatchling Mortality Threatens Survival of Eastern Pacific Leatherback Turtles

Egg-burying reptiles need relatively stable temperature and humidity in the substrate surrounding their eggs for successful development and hatchling emergence. Here we show that egg and hatchling mortality of leatherback turtles (Dermochelys coriacea) in northwest Costa Rica were affected by climatic variability (precipitation and air temperature) driven by the El Niño Southern Oscillation (ENSO). Drier and warmer conditions associated with El Niño increased egg and hatchling mortality. The fourth assessment report of the Intergovernmental Panel on Climate Change (IPCC) projects a warming and drying in Central America and other regions of the World, under the SRES A2 development scenario. Using projections from an ensemble of global climate models contributed to the IPCC report, we project that egg and hatchling survival will rapidly decline in the region over the next 100 years by ∼50–60%, due to warming and drying in northwestern Costa Rica, threatening the survival of leatherback turtles. Warming and drying trends may also threaten the survival of sea turtles in other areas affected by similar climate changes

Embryonic Death Is Linked to Maternal Identity in the Leatherback Turtle (Dermochelys coriacea)

Leatherback turtles have an average global hatching success rate of ∼50%, lower than other marine turtle species. Embryonic death has been linked to environmental factors such as precipitation and temperature, although, there is still a lot of variability that remains to be explained. We examined how nesting season, the time of nesting each season, the relative position of each clutch laid by each female each season, maternal identity and associated factors such as reproductive experience of the female (new nester versus remigrant) and period of egg retention between clutches (interclutch interval) affected hatching success and stage of embryonic death in failed eggs of leatherback turtles nesting at Playa Grande, Costa Rica. Data were collected during five nesting seasons from 2004/05 to 2008/09. Mean hatching success was 50.4%. Nesting season significantly influenced hatching success in addition to early and late stage embryonic death. Neither clutch position nor nesting time during the season had a significant affect on hatching success or the stage of embryonic death. Some leatherback females consistently produced nests with higher hatching success rates than others. Remigrant females arrived earlier to nest, produced more clutches and had higher rates of hatching success than new nesters. Reproductive experience did not affect stage of death or the duration of the interclutch interval. The length of interclutch interval had a significant affect on the proportion of eggs that failed in each clutch and the developmental stage they died at. Intrinsic factors such as maternal identity are playing a role in affecting embryonic death in the leatherback turtle

Long-Term Climate Forcing in Loggerhead Sea Turtle Nesting

The long-term variability of marine turtle populations remains poorly understood, limiting science and management. Here we use basin-scale climate indices and regional surface temperatures to estimate loggerhead sea turtle (Caretta caretta) nesting at a variety of spatial and temporal scales. Borrowing from fisheries research, our models investigate how oceanographic processes influence juvenile recruitment and regulate population dynamics. This novel approach finds local populations in the North Pacific and Northwest Atlantic are regionally synchronized and strongly correlated to ocean conditions—such that climate models alone explain up to 88% of the observed changes over the past several decades. In addition to its performance, climate-based modeling also provides mechanistic forecasts of historical and future population changes. Hindcasts in both regions indicate climatic conditions may have been a factor in recent declines, but future forecasts are mixed. Available climatic data suggests the Pacific population will be significantly reduced by 2040, but indicates the Atlantic population may increase substantially. These results do not exonerate anthropogenic impacts, but highlight the significance of bottom-up oceanographic processes to marine organisms. Future studies should consider environmental baselines in assessments of marine turtle population variability and persistence

Global Conservation Priorities for Marine Turtles

Where conservation resources are limited and conservation targets are diverse, robust yet flexible priority-setting frameworks are vital. Priority-setting is especially important for geographically widespread species with distinct populations subject to multiple threats that operate on different spatial and temporal scales. Marine turtles are widely distributed and exhibit intra-specific variations in population sizes and trends, as well as reproduction and morphology. However, current global extinction risk assessment frameworks do not assess conservation status of spatially and biologically distinct marine turtle Regional Management Units (RMUs), and thus do not capture variations in population trends, impacts of threats, or necessary conservation actions across individual populations. To address this issue, we developed a new assessment framework that allowed us to evaluate, compare and organize marine turtle RMUs according to status and threats criteria. Because conservation priorities can vary widely (i.e. from avoiding imminent extinction to maintaining long-term monitoring efforts) we developed a “conservation priorities portfolio” system using categories of paired risk and threats scores for all RMUs (n = 58). We performed these assessments and rankings globally, by species, by ocean basin, and by recognized geopolitical bodies to identify patterns in risk, threats, and data gaps at different scales. This process resulted in characterization of risk and threats to all marine turtle RMUs, including identification of the world's 11 most endangered marine turtle RMUs based on highest risk and threats scores. This system also highlighted important gaps in available information that is crucial for accurate conservation assessments. Overall, this priority-setting framework can provide guidance for research and conservation priorities at multiple relevant scales, and should serve as a model for conservation status assessments and priority-setting for widespread, long-lived taxa

Male hatchling production in sea turtles from one of the world’s largest marine protected areas, the Chagos Archipelago

Incubation temperatures at turtle nest depths and implications for hatchling sex ratios of hawksbill turtles (Eretmochelys imbricata) and green turtles (Chelonia mydas) nesting in the Chagos Archipelago, Western Indian Ocean are reported and compared to similar measurements at rookeries in the Atlantic and Caribbean. During 2012-2014, temperature loggers were buried at depths and in beach zones representative of turtle nesting sites in Diego Garcia. Data collected for 12,546 days revealed seasonal and spatial patterns of sand temperature. Depth effects were minimal, perhaps modulated by shade from vegetation. Coolest and warmest temperatures were recorded in the sites heavily shaded in vegetation during the austral winter and in sites partially shaded in vegetation during summer respectively. Overall, sand temperatures were relatively cool during the nesting seasons of both species which would likely produce fairly balanced hatchling sex ratios of 53% and 63% male hatchlings, respectively, for hawksbill and green turtles. This result contrasts with the predominantly high female skew reported for offspring at most rookeries around the globe and highlights how local beach characteristics can drive incubation temperatures. Our evidence suggests that sites characterized by heavy shade associated with intact natural vegetation are likely to provide conditions suitable for male hatchling production in a warming world

Short-term gain, long-term loss: How a widely-used conservation tool could further threaten sea turtles

Este artículo contiene, 9 páginas, 4 figuras, 2 tablas.Sea turtles nest on tropical and subtropical beaches, where developmental success of egg clutches depends on nest temperature. Higher nest temperatures increase embryo and hatchling mortalities and produce female hatchlings. Nest shading has been used on some beaches to reduce nest temperatures, and thereby increase number of hatchlings and reduce female-biased sex ratios. We modeled short- and long-term effects of reducing mean nest temperatures on a leatherback turtle (Dermochelys coriacea) population for which the effect of temperature on sex ratios and emergence success (# hatchlings emerged/ # eggs) is well-established. We simulated mean nest temperature reductions of − 0.5 ◦C, − 1 ◦C, − 1.5 ◦C and − 2 ◦C in relation to current mean (30.4 ◦C) and projected population responses over 100 years. Additionally, we run climate change simulations of +0.5 ◦C, +1.0 ◦C and +2.0 ◦C to assess if shading could be needed after passing a certain threshold. Emergence success increased with reduced nest temperatures. However, lowering nest temperatures ultimately caused long-term declines in number of nesting females and total population size, because the number of female hatchlings was reduced. Because hatcheries are a widely-used conservation tool, caution must be used to avoid reducing the number of female hatchlings by lowering nest temperatures. Nest cooling may only be needed under critically low hatchling production and extremely biased female sex ratios that we only found at +2.0 ◦C. If nest shading is to be used, it should be applied strategically to optimize hatchling production with natural sex ratios to achieve both short-term conservation goals and long-term population sustainability.Funding for this study came from the Earthwatch Institute, The Leatherback Trust, the Disney Conservation Fund and the Spanish Ministry of Science (CGL2017-85210) (MICINN/ FEDER, UE).Peer reviewe