Bioweather: Locusts, Worms, and Emerging Diseases

1. BIOWEATHER Pests: locusts Parasites: worms, flukes and spirochetes Diseases: ‘emerging’ viruses “Feeling under the weather?”

2. Locusts and grasshoppers in Africa

3. Desert locusts Locusts eat their own weight (about 4 g) in plant matter per day; a swarm may consist of a billion insects, and 100 swarms may be on the move during a plague (eating 400 kilotons per day). A swarm can fly 300 km in one day, remain afloat out at sea (and take off again), and remain active even when covered by snow.

4. juvenile egg solitary hopper gregarious locust Source: BBC website

6. Last major locust plague (1987-89) Outbreak: 1967-68. Drought in Africa in 1970’s and early 80’s produced a recession in the locust cycle. Heavy rains in 1987-89. In Jan. 1987 large swarms formed in Saudi Arabia. Despite the Saudis’ massive control efforts some of the swarms crossed the Red Sea and gradually moved west to Mauritania and north to Algeria. Western Sahara had heavy rains, and threat to the states in North Africa was so grave that Morocco deployed 200 000 soldiers to combat the swarms. Strong winds aloft (associated with Hurricane Joan) carried some of these locusts across the Atlantic to the Caribbean in October 1988. They reached as far west as Jamaica.

7. Upsurges in 1990’s 1996-1998: Local upsurge in Red Sea Basin (from Yemen - Saudi Arabia to Sudan - Ethiopia - Somalia -Eritrea)

8. a b 2004 outbreak Nov. CYPRUS, EGYPT c map of outbreak b) swarms in Mauritania Aerial spraying in the western Sahara Source: BBC website

9. Monthly snapshots of outbreaks from Nov. 2003-Nov. 2004 gregarious adults gregarious juveniles

10. Rainfall and the Australian plague locust 2004 plague Scale of outbreak Sources: BBC website; www.affa.gov.au; www.bom.gov.au/silo/products/cli_chg

11. Combating locusts • Good news: • Prediction of swarm development and movements much easier with satellites which can identify areas of new plant growth and wind patterns in remote desert areas. • Aerial spraying of young (pre-swarm) populations with insecticide (e.g. malathion) is still effective. • New biopesticide (Metarhizum fungus = “Green Muscle”) kills locusts and grasshoppers in 3 - 4 weeks. • Trigger for gregarious behaviour (hind leg stimulation!) recently identified; may lead to suppression techniques. • Locusts are more nutritious than beef - “Cooking with Sky Prawns” (20 recipes for cooking locusts from Australia)

12. Combating locusts • Bad news: • Highly cyclical nature leads to poor maintenance of surveillance and control equipment during recessions. • Political conflicts create refuge areas for swarms: The western Sahara desert is littered with land mines from the Polisario war.Morocco-Algeria-Libya are reluctant to cooperate;The Sudan is currently in the midst of a civil war; locust control is not a priority for the local government or for international humanitarian agencies.

14. Malaria (Ital: “bad air”) Currently: ~3 000 M people at risk; ~50% of the world’s population; 300-500 M cases; ~80% in sub-Saharan Africa) Deaths: ~1 M annually Vector: transmitted by bites of female mosquitoes in the genusAnopheles (50-60 of the >300 species), usually at night. Parasites: Four species of Plasmodium. P. falciparum causes the most severe symptoms. Symptoms: high fever, dehydration, death in severe cases

15. Global incidence of malaria Map area equivalent to cases per 100 people (92% of all cases in Africa) Source: www.worldmapper.org/posters/worldmapper_map229_ver5.pdf

16. Role of climate in malaria outbreaks Moisture: Breeding success of mosquitoes is maximized in nutrient-rich pools; populations are most abundant in wet weather. Too much rain, however flushes breeding pools and reduces mosquito populations. At temperatures between 25-30°C the malarial parasites and mosquito larvae mature quickly, the adult mosquitoes live longer, and female mosquitoes feed more frequently. The transmission cycle is <30 days under these conditions.

17. Climate and malaria outbreaks Weekly malaria prevalence in Niger for the period 2001-2003, and average monthly precipitation in the Sahel (thick blue line) rain >> pools >> evaporation >> nutrient enrichment >> mosquito breeding

19. 1000 1500 >2000 Summer monsoon Malaria epidemic: Sri Lanka (Ceylon) 1934-5 Drought in 1934-5 resulted in major epidemic in south. 30% of population fell ill; 80,000 died. Illustrates Ross’s “math of malaria” (~25d fever cycle) Malaria was hyperendemic in the dry north of island but rare in the wet south (heavy rains flush mosquito larvae away). Southern population had little natural immunity. 1000 100 100 1 cases 0 25 50 75 days

21. Malaria resurgence ….. and decline 2005-6 ~10 000 cases in South Africa 2006-7 ~3 000 cases in South Africa

22. The demise of malaria in the USA (1882-1946)

23. Why was malaria widespread in northern Europe in the LIA? Little Ice Age from: Reiter, P. 2000. "From Shakespeare to Defoe: Malaria in England during the Little Ice Age” Emerging Infectious Diseases vol. 6

24. Viral disease transmission Ecology of flavivirus outbreaks (e.g. dengue, West Nile encephalitis) Ecology of bunyavirus outbreaks (e.g. sin nombre) Climate and viral disease

25. Emerging viruses FamilyDisease Vector and Reservoir

27. West Nile virus • West Nile virus is a strain of flavivrus, closely related to Japanese encephalitis. Previously reported from Africa and adjacent areas of southern Europe and western Asia. Previous outbreaks in Israel, France and S. Africa. and Romania (1996; 450 cases, 39 deaths). • It joins at least four other encephalitis viruses in North America, one of which [St. Louis encephalitis] is widespread. • Likely introduced into N. America by an infected international traveler or as a result of the importation of exotic birds.

29. fever, aches, stupor, (brain lesions, coma, paralysis, death?) direct transmission?

31. 1999 1999 to 2001

33. November, 2003 Total number of cases by state November, 2004

34. WNV cases - Canada Is the WNV threat over in N. America? *related to travel outside province

35. Impactors Geog 312 Ian Hutchinson The ThreatRisk AssessmentProtection(?)

36. Asteroids • Asteroid orbits continuously modified by gravitational perturbation of asteroid belt. • About 2000 asteroids currently have orbits that cross that of Earth (= NEO’s :Near Earth Objects). • Orbital trajectories of 200 NEO’s are known; i.e. the paths of 90% of the asteroids that threaten Earth are unknown. • Largest NEO’s have diameters of about 8 km; the orbits of about 35% of asteroids >5 km diameter are known.

37. Comets • About 10-20% of comets (piles of rubble and ice with tail =“coma”) are in Earth-crossing orbits. • Some 700 long-period comets (T>200 yrs) known. • Periodic comets (T≤200 yrs) - 95% have lost their coma (= “stealth comets”) 25 known, 1500 > 1 km diameter may exist. • Our first warning is likely to be their initial entry into Earth’s atmosphere.

38. Effects • Direct (predominantly local)Impact crater plus blast-wave and firestorm • Indirect effects (may be global)Dust veil (large impactors)Acid rain (large impactors)Tsunami (oceanic impacts)

39. Impact craters on Mercuryindicative of the protective effects of Earth’s atmosphere

40. Impactors • <10 m diameter - burnup in atmosphere. • Category 1: 10-100 m diameter - disintegrate in atmosphere; exploding fragments create “airburst” (e.g. Tunguska event). • Category 2: 100 m - 1 km diameter - capable of striking surface, forming impact craters, effects local (e.g. Meteor Crater, AZ). • Category 3: > 1 km in diameter may cause severe global effects (e.g. Chicxulub impactor, Mexico)

41. Category 1: Tunguska • 50-60 m diameter stony meteor? exploded in June 1908 above central Siberia. Energy release ~ 10-30 MT TNT (~1 000 – 3 000 Hiroshima bombs) • Radius of destruction: 25 km (= 2 000 km2). • Recorded by seismograms in Irkutsk and barograms in London.

42. Tunguska impact area from a local perspective First photos of the effects of the Tunguska fireball were taken by a Soviet expedition in the 1920’s, more than a decade after the event.

43. 1200 m wide, 180 m deep Category 2:Meteor (a.k.a. Barrington) Crater, AZ. Impact occurred about 50 000 years ago; it is likely that all plant and animal life within 10 km of the impact site was vapourized.

44. Category 3

45. Category 3 Crater 10 - 15x diameter of impactor Veil of dust in atmosphere for months/years Reduced sunlight Reduced photosynthesis Lowered global temperature Polar and temperate areas uninhabitable Food chain collapses

46. Category 3 Very high temperatures at impact site Firestorm spreads from impact site N2 in atmosphere burns Intense smokefrom firestorm: reduced sunlight, etc. Nitric acid produced; acidic precipitation Reduced photosynthesis; food chain collapses

47. Rock hammer for scale Sandstone Tertiary Clay Coal Cretaceous Shale Asteroid impact dust deposit (clay layer) marking K-T boundary at 65 Ma BP in Colorado, 2500 km from impact site.

48. Risk Assessment:Spacewatch Project • Initiated at the University of Arizona in early 1980’s, the Spacewatch project involves automated searches of the sky for 20 nights per month for new asteroids (particularly NEOs) and short-period comets. Now includes cooperative efforts with other observatories in North America, Europe and Australia.

49. Hazardclassification The scale value PS is given by PS = log10 [PI / (fB. DT)], where PI is the impact probability of the event in question and DT is the time until the potential event, measured in years. The annual background impact frequency, fB = 0.03 . E-4/5 is the annual probability of an impact event with energy (E, in megatons of TNT) at least as large as the event in question. The Palermo scale was developed to categorize potential impact risks. Intended for use by specialists.

50. Hazardclassification The scale was devised by delegates to an international symposium in Torino (Turin; Italy) in 1999 as a means of communicating risk to the public.