Related by context. Frequent words. (Click for all words.) 60 gray squirrels 58 ragwort 57 Aedes aegypti mosquito 56 bluetongue virus 55 tiger mosquito 55 tsetse flies 54 citrus greening disease 54 parasite 54 chytrid fungus 54 varroa mites 53 varroa mite 52 Aedes mosquitoes 52 midge 52 falciparum malaria 52 pathogen 52 gray squirrel 52 fungus 52 Yersinia pestis 52 parasitic worm 52 sandflies 52 fireblight 52 parasitic worms 51 Aedes mosquito 51 foxes 51 microbial pathogens 51 funguses 51 MRSA superbug 51 invasive insect 50 ladybird 50 Parvovirus 50 virulent strains 50 tsetse fly 50 ladybirds 50 parasites 50 bilharzia 50 Didymo 50 disease 50 badgers 50 stoats 50 fungal disease 50 mites 50 ash borers 50 anaplasmosis 50 potato blight 50 mutated strain 50 whitefly 49 mealybug 49 Bubonic plague 49 Toxoplasma gondii 49 wildfowl 49 Toxoplasma 49 Rocky Mountain Spotted Fever 49 leaf curl 49 Cane toads 49 highly pathogenic H#N# virus 49 sawfly 49 bacilli 49 Staph bacteria 49 superbugs 49 stoat 49 E.coli O# 49 avian influenza H#N# 49 virus 49 fungal pathogens 49 protozoan 49 melioidosis 49 P. falciparum 48 mealybugs 48 midges 48 Migrating birds 48 T. gondii 48 beetle 48 Nipah virus 48 Wild boar 48 ehrlichiosis 48 parasitic wasps 48 bacterial pathogen 48 poxvirus 48 insects 48 quolls 48 bluetongue disease 48 psyllids 48 viruses 48 invasive pest 48 herpes viruses 48 Aphids 48 bollworms 48 Midges 48 Larvae 48 avian flu viruses 48 fungal spores 48 disease vCJD 48 C.difficile 48 insect pests 48 bumblebees 48 roe deer 48 guillemots 48 sea lampreys 48 Hantavirus 48 infectious prions 48 pollinating insects