befallen
to infest
To spread negatively over something or someone and damage it. Typically used for diseases, pests, or parasites.
Die Kartoffeln sind von einem Pilz befallen.
The potatoes are infested with a fungus.

to infest / overcome
Loading your saved state.
to infest
To spread negatively over something or someone and damage it. Typically used for diseases, pests, or parasites.
Die Kartoffeln sind von einem Pilz befallen.
The potatoes are infested with a fungus.

'Befallen' (to infest / overcome) is an inseparable verb. The prefix 'be-' remains firmly attached to the verb stem 'fallen' in all tenses and sentence constructions.
Ein seltsames Gefühl befiel ihn, als er das leere Haus betrat.
A strange feeling overcame him when he entered the empty house.
This verb always requires an accusative object. The object is the person or thing that is affected by something (the subject).
Die Krankheit befällt vor allem ältere Menschen.
The disease mainly affects older people.
You can recognize the meaning from the subject of the sentence. If it refers to pests or diseases, the first meaning is intended. If it refers to a feeling, the second meaning is intended.
Der Schimmel hat die Wände befallen.
The mold has infested the walls.
Especially with diseases and pests, the passive form with 'sein' (to be) is often used. The thing that is affected becomes the subject of the sentence.
Viele Apfelbäume in der Region sind von einer neuen Krankheit befallen.
Many apple trees in the region are infested with a new disease.
When 'befallen' (to overcome) is used with a feeling, it often sounds elevated or literary. It describes a sudden, strong, and often passive experience of the feeling.
Eine tiefe Traurigkeit befiel ihn nach der Nachricht.
A deep sadness overcame him after the news.
to record / grasp
'erfassen' and 'befallen' can both describe a strong feeling suddenly coming over someone. 'erfassen' is somewhat more general and can also refer to strong forces of nature or various feelings. 'befallen' usually sounds negative and is especially suitable for fear, doubt, or unease. It presents the feeling almost like something that attacks someone. In this sense, the words are similar, but 'befallen' is narrower and more strongly negative. 'befallen' is also used for diseases or pests; in that meaning, 'erfassen' does not fit.

Vor der Prüfung befiel ihn ein unangenehmer Zweifel.
Before the exam, he was overcome by an unpleasant doubt.
Als der Sturm plötzlich stärker wurde, erfasste die Kinder große Angst.
When the storm suddenly grew stronger, great fear swept over the children.